1 // random number generation (out of line) -*- C++ -*-
2 
3 // Copyright (C) 2009-2019 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library.  This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file bits/random.tcc
26  *  This is an internal header file, included by other library headers.
27  *  Do not attempt to use it directly. @headername{random}
28  */
29 
30 #ifndef _RANDOM_TCC
31 #define _RANDOM_TCC 1
32 
33 #include <numeric> // std::accumulate and std::partial_sum
34 
35 namespace std _GLIBCXX_VISIBILITY(default)
36 {
37 _GLIBCXX_BEGIN_NAMESPACE_VERSION
38 
39   /*
40    * (Further) implementation-space details.
41    */
42   namespace __detail
43   {
44     // General case for x = (ax + c) mod m -- use Schrage's algorithm
45     // to avoid integer overflow.
46     //
47     // Preconditions:  a > 0, m > 0.
48     //
49     // Note: only works correctly for __m % __a < __m / __a.
50     template<typename _Tp, _Tp __m, _Tp __a, _Tp __c>
51       _Tp
52       _Mod<_Tp, __m, __a, __c, false, true>::
53       __calc(_Tp __x)
54       {
55 	if (__a == 1)
56 	  __x %= __m;
57 	else
58 	  {
59 	    static const _Tp __q = __m / __a;
60 	    static const _Tp __r = __m % __a;
61 
62 	    _Tp __t1 = __a * (__x % __q);
63 	    _Tp __t2 = __r * (__x / __q);
64 	    if (__t1 >= __t2)
65 	      __x = __t1 - __t2;
66 	    else
67 	      __x = __m - __t2 + __t1;
68 	  }
69 
70 	if (__c != 0)
71 	  {
72 	    const _Tp __d = __m - __x;
73 	    if (__d > __c)
74 	      __x += __c;
75 	    else
76 	      __x = __c - __d;
77 	  }
78 	return __x;
79       }
80 
81     template<typename _InputIterator, typename _OutputIterator,
82 	     typename _Tp>
83       _OutputIterator
84       __normalize(_InputIterator __first, _InputIterator __last,
85 		  _OutputIterator __result, const _Tp& __factor)
86       {
87 	for (; __first != __last; ++__first, ++__result)
88 	  *__result = *__first / __factor;
89 	return __result;
90       }
91 
92   } // namespace __detail
93 
94   template<typename _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
95     constexpr _UIntType
96     linear_congruential_engine<_UIntType, __a, __c, __m>::multiplier;
97 
98   template<typename _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
99     constexpr _UIntType
100     linear_congruential_engine<_UIntType, __a, __c, __m>::increment;
101 
102   template<typename _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
103     constexpr _UIntType
104     linear_congruential_engine<_UIntType, __a, __c, __m>::modulus;
105 
106   template<typename _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
107     constexpr _UIntType
108     linear_congruential_engine<_UIntType, __a, __c, __m>::default_seed;
109 
110   /**
111    * Seeds the LCR with integral value @p __s, adjusted so that the
112    * ring identity is never a member of the convergence set.
113    */
114   template<typename _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
115     void
116     linear_congruential_engine<_UIntType, __a, __c, __m>::
seed(result_type __s)117     seed(result_type __s)
118     {
119       if ((__detail::__mod<_UIntType, __m>(__c) == 0)
120 	  && (__detail::__mod<_UIntType, __m>(__s) == 0))
121 	_M_x = 1;
122       else
123 	_M_x = __detail::__mod<_UIntType, __m>(__s);
124     }
125 
126   /**
127    * Seeds the LCR engine with a value generated by @p __q.
128    */
129   template<typename _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
130     template<typename _Sseq>
131       auto
132       linear_congruential_engine<_UIntType, __a, __c, __m>::
seed(_Sseq & __q)133       seed(_Sseq& __q)
134       -> _If_seed_seq<_Sseq>
135       {
136 	const _UIntType __k0 = __m == 0 ? std::numeric_limits<_UIntType>::digits
137 	                                : std::__lg(__m);
138 	const _UIntType __k = (__k0 + 31) / 32;
139 	uint_least32_t __arr[__k + 3];
140 	__q.generate(__arr + 0, __arr + __k + 3);
141 	_UIntType __factor = 1u;
142 	_UIntType __sum = 0u;
143 	for (size_t __j = 0; __j < __k; ++__j)
144 	  {
145 	    __sum += __arr[__j + 3] * __factor;
146 	    __factor *= __detail::_Shift<_UIntType, 32>::__value;
147 	  }
148 	seed(__sum);
149       }
150 
151   template<typename _UIntType, _UIntType __a, _UIntType __c, _UIntType __m,
152 	   typename _CharT, typename _Traits>
153     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const linear_congruential_engine<_UIntType,__a,__c,__m> & __lcr)154     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
155 	       const linear_congruential_engine<_UIntType,
156 						__a, __c, __m>& __lcr)
157     {
158       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
159       typedef typename __ostream_type::ios_base    __ios_base;
160 
161       const typename __ios_base::fmtflags __flags = __os.flags();
162       const _CharT __fill = __os.fill();
163       __os.flags(__ios_base::dec | __ios_base::fixed | __ios_base::left);
164       __os.fill(__os.widen(' '));
165 
166       __os << __lcr._M_x;
167 
168       __os.flags(__flags);
169       __os.fill(__fill);
170       return __os;
171     }
172 
173   template<typename _UIntType, _UIntType __a, _UIntType __c, _UIntType __m,
174 	   typename _CharT, typename _Traits>
175     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,linear_congruential_engine<_UIntType,__a,__c,__m> & __lcr)176     operator>>(std::basic_istream<_CharT, _Traits>& __is,
177 	       linear_congruential_engine<_UIntType, __a, __c, __m>& __lcr)
178     {
179       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
180       typedef typename __istream_type::ios_base    __ios_base;
181 
182       const typename __ios_base::fmtflags __flags = __is.flags();
183       __is.flags(__ios_base::dec);
184 
185       __is >> __lcr._M_x;
186 
187       __is.flags(__flags);
188       return __is;
189     }
190 
191 
192   template<typename _UIntType,
193 	   size_t __w, size_t __n, size_t __m, size_t __r,
194 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
195 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
196 	   _UIntType __f>
197     constexpr size_t
198     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
199 			    __s, __b, __t, __c, __l, __f>::word_size;
200 
201   template<typename _UIntType,
202 	   size_t __w, size_t __n, size_t __m, size_t __r,
203 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
204 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
205 	   _UIntType __f>
206     constexpr size_t
207     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
208 			    __s, __b, __t, __c, __l, __f>::state_size;
209 
210   template<typename _UIntType,
211 	   size_t __w, size_t __n, size_t __m, size_t __r,
212 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
213 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
214 	   _UIntType __f>
215     constexpr size_t
216     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
217 			    __s, __b, __t, __c, __l, __f>::shift_size;
218 
219   template<typename _UIntType,
220 	   size_t __w, size_t __n, size_t __m, size_t __r,
221 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
222 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
223 	   _UIntType __f>
224     constexpr size_t
225     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
226 			    __s, __b, __t, __c, __l, __f>::mask_bits;
227 
228   template<typename _UIntType,
229 	   size_t __w, size_t __n, size_t __m, size_t __r,
230 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
231 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
232 	   _UIntType __f>
233     constexpr _UIntType
234     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
235 			    __s, __b, __t, __c, __l, __f>::xor_mask;
236 
237   template<typename _UIntType,
238 	   size_t __w, size_t __n, size_t __m, size_t __r,
239 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
240 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
241 	   _UIntType __f>
242     constexpr size_t
243     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
244 			    __s, __b, __t, __c, __l, __f>::tempering_u;
245 
246   template<typename _UIntType,
247 	   size_t __w, size_t __n, size_t __m, size_t __r,
248 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
249 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
250 	   _UIntType __f>
251     constexpr _UIntType
252     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
253 			    __s, __b, __t, __c, __l, __f>::tempering_d;
254 
255   template<typename _UIntType,
256 	   size_t __w, size_t __n, size_t __m, size_t __r,
257 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
258 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
259 	   _UIntType __f>
260     constexpr size_t
261     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
262 			    __s, __b, __t, __c, __l, __f>::tempering_s;
263 
264   template<typename _UIntType,
265 	   size_t __w, size_t __n, size_t __m, size_t __r,
266 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
267 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
268 	   _UIntType __f>
269     constexpr _UIntType
270     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
271 			    __s, __b, __t, __c, __l, __f>::tempering_b;
272 
273   template<typename _UIntType,
274 	   size_t __w, size_t __n, size_t __m, size_t __r,
275 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
276 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
277 	   _UIntType __f>
278     constexpr size_t
279     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
280 			    __s, __b, __t, __c, __l, __f>::tempering_t;
281 
282   template<typename _UIntType,
283 	   size_t __w, size_t __n, size_t __m, size_t __r,
284 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
285 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
286 	   _UIntType __f>
287     constexpr _UIntType
288     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
289 			    __s, __b, __t, __c, __l, __f>::tempering_c;
290 
291   template<typename _UIntType,
292 	   size_t __w, size_t __n, size_t __m, size_t __r,
293 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
294 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
295 	   _UIntType __f>
296     constexpr size_t
297     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
298 			    __s, __b, __t, __c, __l, __f>::tempering_l;
299 
300   template<typename _UIntType,
301 	   size_t __w, size_t __n, size_t __m, size_t __r,
302 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
303 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
304 	   _UIntType __f>
305     constexpr _UIntType
306     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
307 			    __s, __b, __t, __c, __l, __f>::
308                                               initialization_multiplier;
309 
310   template<typename _UIntType,
311 	   size_t __w, size_t __n, size_t __m, size_t __r,
312 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
313 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
314 	   _UIntType __f>
315     constexpr _UIntType
316     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
317 			    __s, __b, __t, __c, __l, __f>::default_seed;
318 
319   template<typename _UIntType,
320 	   size_t __w, size_t __n, size_t __m, size_t __r,
321 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
322 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
323 	   _UIntType __f>
324     void
325     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
326 			    __s, __b, __t, __c, __l, __f>::
seed(result_type __sd)327     seed(result_type __sd)
328     {
329       _M_x[0] = __detail::__mod<_UIntType,
330 	__detail::_Shift<_UIntType, __w>::__value>(__sd);
331 
332       for (size_t __i = 1; __i < state_size; ++__i)
333 	{
334 	  _UIntType __x = _M_x[__i - 1];
335 	  __x ^= __x >> (__w - 2);
336 	  __x *= __f;
337 	  __x += __detail::__mod<_UIntType, __n>(__i);
338 	  _M_x[__i] = __detail::__mod<_UIntType,
339 	    __detail::_Shift<_UIntType, __w>::__value>(__x);
340 	}
341       _M_p = state_size;
342     }
343 
344   template<typename _UIntType,
345 	   size_t __w, size_t __n, size_t __m, size_t __r,
346 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
347 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
348 	   _UIntType __f>
349     template<typename _Sseq>
350       auto
351       mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
352 			      __s, __b, __t, __c, __l, __f>::
seed(_Sseq & __q)353       seed(_Sseq& __q)
354       -> _If_seed_seq<_Sseq>
355       {
356 	const _UIntType __upper_mask = (~_UIntType()) << __r;
357 	const size_t __k = (__w + 31) / 32;
358 	uint_least32_t __arr[__n * __k];
359 	__q.generate(__arr + 0, __arr + __n * __k);
360 
361 	bool __zero = true;
362 	for (size_t __i = 0; __i < state_size; ++__i)
363 	  {
364 	    _UIntType __factor = 1u;
365 	    _UIntType __sum = 0u;
366 	    for (size_t __j = 0; __j < __k; ++__j)
367 	      {
368 		__sum += __arr[__k * __i + __j] * __factor;
369 		__factor *= __detail::_Shift<_UIntType, 32>::__value;
370 	      }
371 	    _M_x[__i] = __detail::__mod<_UIntType,
372 	      __detail::_Shift<_UIntType, __w>::__value>(__sum);
373 
374 	    if (__zero)
375 	      {
376 		if (__i == 0)
377 		  {
378 		    if ((_M_x[0] & __upper_mask) != 0u)
379 		      __zero = false;
380 		  }
381 		else if (_M_x[__i] != 0u)
382 		  __zero = false;
383 	      }
384 	  }
385         if (__zero)
386           _M_x[0] = __detail::_Shift<_UIntType, __w - 1>::__value;
387 	_M_p = state_size;
388       }
389 
390   template<typename _UIntType, size_t __w,
391 	   size_t __n, size_t __m, size_t __r,
392 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
393 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
394 	   _UIntType __f>
395     void
396     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
397 			    __s, __b, __t, __c, __l, __f>::
_M_gen_rand(void)398     _M_gen_rand(void)
399     {
400       const _UIntType __upper_mask = (~_UIntType()) << __r;
401       const _UIntType __lower_mask = ~__upper_mask;
402 
403       for (size_t __k = 0; __k < (__n - __m); ++__k)
404         {
405 	  _UIntType __y = ((_M_x[__k] & __upper_mask)
406 			   | (_M_x[__k + 1] & __lower_mask));
407 	  _M_x[__k] = (_M_x[__k + __m] ^ (__y >> 1)
408 		       ^ ((__y & 0x01) ? __a : 0));
409         }
410 
411       for (size_t __k = (__n - __m); __k < (__n - 1); ++__k)
412 	{
413 	  _UIntType __y = ((_M_x[__k] & __upper_mask)
414 			   | (_M_x[__k + 1] & __lower_mask));
415 	  _M_x[__k] = (_M_x[__k + (__m - __n)] ^ (__y >> 1)
416 		       ^ ((__y & 0x01) ? __a : 0));
417 	}
418 
419       _UIntType __y = ((_M_x[__n - 1] & __upper_mask)
420 		       | (_M_x[0] & __lower_mask));
421       _M_x[__n - 1] = (_M_x[__m - 1] ^ (__y >> 1)
422 		       ^ ((__y & 0x01) ? __a : 0));
423       _M_p = 0;
424     }
425 
426   template<typename _UIntType, size_t __w,
427 	   size_t __n, size_t __m, size_t __r,
428 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
429 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
430 	   _UIntType __f>
431     void
432     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
433 			    __s, __b, __t, __c, __l, __f>::
discard(unsigned long long __z)434     discard(unsigned long long __z)
435     {
436       while (__z > state_size - _M_p)
437 	{
438 	  __z -= state_size - _M_p;
439 	  _M_gen_rand();
440 	}
441       _M_p += __z;
442     }
443 
444   template<typename _UIntType, size_t __w,
445 	   size_t __n, size_t __m, size_t __r,
446 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
447 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
448 	   _UIntType __f>
449     typename
450     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
451 			    __s, __b, __t, __c, __l, __f>::result_type
452     mersenne_twister_engine<_UIntType, __w, __n, __m, __r, __a, __u, __d,
453 			    __s, __b, __t, __c, __l, __f>::
operator ()()454     operator()()
455     {
456       // Reload the vector - cost is O(n) amortized over n calls.
457       if (_M_p >= state_size)
458 	_M_gen_rand();
459 
460       // Calculate o(x(i)).
461       result_type __z = _M_x[_M_p++];
462       __z ^= (__z >> __u) & __d;
463       __z ^= (__z << __s) & __b;
464       __z ^= (__z << __t) & __c;
465       __z ^= (__z >> __l);
466 
467       return __z;
468     }
469 
470   template<typename _UIntType, size_t __w,
471 	   size_t __n, size_t __m, size_t __r,
472 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
473 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
474 	   _UIntType __f, typename _CharT, typename _Traits>
475     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const mersenne_twister_engine<_UIntType,__w,__n,__m,__r,__a,__u,__d,__s,__b,__t,__c,__l,__f> & __x)476     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
477 	       const mersenne_twister_engine<_UIntType, __w, __n, __m,
478 	       __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>& __x)
479     {
480       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
481       typedef typename __ostream_type::ios_base    __ios_base;
482 
483       const typename __ios_base::fmtflags __flags = __os.flags();
484       const _CharT __fill = __os.fill();
485       const _CharT __space = __os.widen(' ');
486       __os.flags(__ios_base::dec | __ios_base::fixed | __ios_base::left);
487       __os.fill(__space);
488 
489       for (size_t __i = 0; __i < __n; ++__i)
490 	__os << __x._M_x[__i] << __space;
491       __os << __x._M_p;
492 
493       __os.flags(__flags);
494       __os.fill(__fill);
495       return __os;
496     }
497 
498   template<typename _UIntType, size_t __w,
499 	   size_t __n, size_t __m, size_t __r,
500 	   _UIntType __a, size_t __u, _UIntType __d, size_t __s,
501 	   _UIntType __b, size_t __t, _UIntType __c, size_t __l,
502 	   _UIntType __f, typename _CharT, typename _Traits>
503     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,mersenne_twister_engine<_UIntType,__w,__n,__m,__r,__a,__u,__d,__s,__b,__t,__c,__l,__f> & __x)504     operator>>(std::basic_istream<_CharT, _Traits>& __is,
505 	       mersenne_twister_engine<_UIntType, __w, __n, __m,
506 	       __r, __a, __u, __d, __s, __b, __t, __c, __l, __f>& __x)
507     {
508       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
509       typedef typename __istream_type::ios_base    __ios_base;
510 
511       const typename __ios_base::fmtflags __flags = __is.flags();
512       __is.flags(__ios_base::dec | __ios_base::skipws);
513 
514       for (size_t __i = 0; __i < __n; ++__i)
515 	__is >> __x._M_x[__i];
516       __is >> __x._M_p;
517 
518       __is.flags(__flags);
519       return __is;
520     }
521 
522 
523   template<typename _UIntType, size_t __w, size_t __s, size_t __r>
524     constexpr size_t
525     subtract_with_carry_engine<_UIntType, __w, __s, __r>::word_size;
526 
527   template<typename _UIntType, size_t __w, size_t __s, size_t __r>
528     constexpr size_t
529     subtract_with_carry_engine<_UIntType, __w, __s, __r>::short_lag;
530 
531   template<typename _UIntType, size_t __w, size_t __s, size_t __r>
532     constexpr size_t
533     subtract_with_carry_engine<_UIntType, __w, __s, __r>::long_lag;
534 
535   template<typename _UIntType, size_t __w, size_t __s, size_t __r>
536     constexpr _UIntType
537     subtract_with_carry_engine<_UIntType, __w, __s, __r>::default_seed;
538 
539   template<typename _UIntType, size_t __w, size_t __s, size_t __r>
540     void
541     subtract_with_carry_engine<_UIntType, __w, __s, __r>::
seed(result_type __value)542     seed(result_type __value)
543     {
544       std::linear_congruential_engine<result_type, 40014u, 0u, 2147483563u>
545 	__lcg(__value == 0u ? default_seed : __value);
546 
547       const size_t __n = (__w + 31) / 32;
548 
549       for (size_t __i = 0; __i < long_lag; ++__i)
550 	{
551 	  _UIntType __sum = 0u;
552 	  _UIntType __factor = 1u;
553 	  for (size_t __j = 0; __j < __n; ++__j)
554 	    {
555 	      __sum += __detail::__mod<uint_least32_t,
556 		       __detail::_Shift<uint_least32_t, 32>::__value>
557 			 (__lcg()) * __factor;
558 	      __factor *= __detail::_Shift<_UIntType, 32>::__value;
559 	    }
560 	  _M_x[__i] = __detail::__mod<_UIntType,
561 	    __detail::_Shift<_UIntType, __w>::__value>(__sum);
562 	}
563       _M_carry = (_M_x[long_lag - 1] == 0) ? 1 : 0;
564       _M_p = 0;
565     }
566 
567   template<typename _UIntType, size_t __w, size_t __s, size_t __r>
568     template<typename _Sseq>
569       auto
570       subtract_with_carry_engine<_UIntType, __w, __s, __r>::
seed(_Sseq & __q)571       seed(_Sseq& __q)
572       -> _If_seed_seq<_Sseq>
573       {
574 	const size_t __k = (__w + 31) / 32;
575 	uint_least32_t __arr[__r * __k];
576 	__q.generate(__arr + 0, __arr + __r * __k);
577 
578 	for (size_t __i = 0; __i < long_lag; ++__i)
579 	  {
580 	    _UIntType __sum = 0u;
581 	    _UIntType __factor = 1u;
582 	    for (size_t __j = 0; __j < __k; ++__j)
583 	      {
584 		__sum += __arr[__k * __i + __j] * __factor;
585 		__factor *= __detail::_Shift<_UIntType, 32>::__value;
586 	      }
587 	    _M_x[__i] = __detail::__mod<_UIntType,
588 	      __detail::_Shift<_UIntType, __w>::__value>(__sum);
589 	  }
590 	_M_carry = (_M_x[long_lag - 1] == 0) ? 1 : 0;
591 	_M_p = 0;
592       }
593 
594   template<typename _UIntType, size_t __w, size_t __s, size_t __r>
595     typename subtract_with_carry_engine<_UIntType, __w, __s, __r>::
596 	     result_type
597     subtract_with_carry_engine<_UIntType, __w, __s, __r>::
operator ()()598     operator()()
599     {
600       // Derive short lag index from current index.
601       long __ps = _M_p - short_lag;
602       if (__ps < 0)
603 	__ps += long_lag;
604 
605       // Calculate new x(i) without overflow or division.
606       // NB: Thanks to the requirements for _UIntType, _M_x[_M_p] + _M_carry
607       // cannot overflow.
608       _UIntType __xi;
609       if (_M_x[__ps] >= _M_x[_M_p] + _M_carry)
610 	{
611 	  __xi = _M_x[__ps] - _M_x[_M_p] - _M_carry;
612 	  _M_carry = 0;
613 	}
614       else
615 	{
616 	  __xi = (__detail::_Shift<_UIntType, __w>::__value
617 		  - _M_x[_M_p] - _M_carry + _M_x[__ps]);
618 	  _M_carry = 1;
619 	}
620       _M_x[_M_p] = __xi;
621 
622       // Adjust current index to loop around in ring buffer.
623       if (++_M_p >= long_lag)
624 	_M_p = 0;
625 
626       return __xi;
627     }
628 
629   template<typename _UIntType, size_t __w, size_t __s, size_t __r,
630 	   typename _CharT, typename _Traits>
631     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const subtract_with_carry_engine<_UIntType,__w,__s,__r> & __x)632     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
633 	       const subtract_with_carry_engine<_UIntType,
634 						__w, __s, __r>& __x)
635     {
636       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
637       typedef typename __ostream_type::ios_base    __ios_base;
638 
639       const typename __ios_base::fmtflags __flags = __os.flags();
640       const _CharT __fill = __os.fill();
641       const _CharT __space = __os.widen(' ');
642       __os.flags(__ios_base::dec | __ios_base::fixed | __ios_base::left);
643       __os.fill(__space);
644 
645       for (size_t __i = 0; __i < __r; ++__i)
646 	__os << __x._M_x[__i] << __space;
647       __os << __x._M_carry << __space << __x._M_p;
648 
649       __os.flags(__flags);
650       __os.fill(__fill);
651       return __os;
652     }
653 
654   template<typename _UIntType, size_t __w, size_t __s, size_t __r,
655 	   typename _CharT, typename _Traits>
656     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,subtract_with_carry_engine<_UIntType,__w,__s,__r> & __x)657     operator>>(std::basic_istream<_CharT, _Traits>& __is,
658 	       subtract_with_carry_engine<_UIntType, __w, __s, __r>& __x)
659     {
660       typedef std::basic_ostream<_CharT, _Traits>  __istream_type;
661       typedef typename __istream_type::ios_base    __ios_base;
662 
663       const typename __ios_base::fmtflags __flags = __is.flags();
664       __is.flags(__ios_base::dec | __ios_base::skipws);
665 
666       for (size_t __i = 0; __i < __r; ++__i)
667 	__is >> __x._M_x[__i];
668       __is >> __x._M_carry;
669       __is >> __x._M_p;
670 
671       __is.flags(__flags);
672       return __is;
673     }
674 
675 
676   template<typename _RandomNumberEngine, size_t __p, size_t __r>
677     constexpr size_t
678     discard_block_engine<_RandomNumberEngine, __p, __r>::block_size;
679 
680   template<typename _RandomNumberEngine, size_t __p, size_t __r>
681     constexpr size_t
682     discard_block_engine<_RandomNumberEngine, __p, __r>::used_block;
683 
684   template<typename _RandomNumberEngine, size_t __p, size_t __r>
685     typename discard_block_engine<_RandomNumberEngine,
686 			   __p, __r>::result_type
687     discard_block_engine<_RandomNumberEngine, __p, __r>::
operator ()()688     operator()()
689     {
690       if (_M_n >= used_block)
691 	{
692 	  _M_b.discard(block_size - _M_n);
693 	  _M_n = 0;
694 	}
695       ++_M_n;
696       return _M_b();
697     }
698 
699   template<typename _RandomNumberEngine, size_t __p, size_t __r,
700 	   typename _CharT, typename _Traits>
701     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const discard_block_engine<_RandomNumberEngine,__p,__r> & __x)702     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
703 	       const discard_block_engine<_RandomNumberEngine,
704 	       __p, __r>& __x)
705     {
706       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
707       typedef typename __ostream_type::ios_base    __ios_base;
708 
709       const typename __ios_base::fmtflags __flags = __os.flags();
710       const _CharT __fill = __os.fill();
711       const _CharT __space = __os.widen(' ');
712       __os.flags(__ios_base::dec | __ios_base::fixed | __ios_base::left);
713       __os.fill(__space);
714 
715       __os << __x.base() << __space << __x._M_n;
716 
717       __os.flags(__flags);
718       __os.fill(__fill);
719       return __os;
720     }
721 
722   template<typename _RandomNumberEngine, size_t __p, size_t __r,
723 	   typename _CharT, typename _Traits>
724     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,discard_block_engine<_RandomNumberEngine,__p,__r> & __x)725     operator>>(std::basic_istream<_CharT, _Traits>& __is,
726 	       discard_block_engine<_RandomNumberEngine, __p, __r>& __x)
727     {
728       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
729       typedef typename __istream_type::ios_base    __ios_base;
730 
731       const typename __ios_base::fmtflags __flags = __is.flags();
732       __is.flags(__ios_base::dec | __ios_base::skipws);
733 
734       __is >> __x._M_b >> __x._M_n;
735 
736       __is.flags(__flags);
737       return __is;
738     }
739 
740 
741   template<typename _RandomNumberEngine, size_t __w, typename _UIntType>
742     typename independent_bits_engine<_RandomNumberEngine, __w, _UIntType>::
743       result_type
744     independent_bits_engine<_RandomNumberEngine, __w, _UIntType>::
operator ()()745     operator()()
746     {
747       typedef typename _RandomNumberEngine::result_type _Eresult_type;
748       const _Eresult_type __r
749 	= (_M_b.max() - _M_b.min() < std::numeric_limits<_Eresult_type>::max()
750 	   ? _M_b.max() - _M_b.min() + 1 : 0);
751       const unsigned __edig = std::numeric_limits<_Eresult_type>::digits;
752       const unsigned __m = __r ? std::__lg(__r) : __edig;
753 
754       typedef typename std::common_type<_Eresult_type, result_type>::type
755 	__ctype;
756       const unsigned __cdig = std::numeric_limits<__ctype>::digits;
757 
758       unsigned __n, __n0;
759       __ctype __s0, __s1, __y0, __y1;
760 
761       for (size_t __i = 0; __i < 2; ++__i)
762 	{
763 	  __n = (__w + __m - 1) / __m + __i;
764 	  __n0 = __n - __w % __n;
765 	  const unsigned __w0 = __w / __n;  // __w0 <= __m
766 
767 	  __s0 = 0;
768 	  __s1 = 0;
769 	  if (__w0 < __cdig)
770 	    {
771 	      __s0 = __ctype(1) << __w0;
772 	      __s1 = __s0 << 1;
773 	    }
774 
775 	  __y0 = 0;
776 	  __y1 = 0;
777 	  if (__r)
778 	    {
779 	      __y0 = __s0 * (__r / __s0);
780 	      if (__s1)
781 		__y1 = __s1 * (__r / __s1);
782 
783 	      if (__r - __y0 <= __y0 / __n)
784 		break;
785 	    }
786 	  else
787 	    break;
788 	}
789 
790       result_type __sum = 0;
791       for (size_t __k = 0; __k < __n0; ++__k)
792 	{
793 	  __ctype __u;
794 	  do
795 	    __u = _M_b() - _M_b.min();
796 	  while (__y0 && __u >= __y0);
797 	  __sum = __s0 * __sum + (__s0 ? __u % __s0 : __u);
798 	}
799       for (size_t __k = __n0; __k < __n; ++__k)
800 	{
801 	  __ctype __u;
802 	  do
803 	    __u = _M_b() - _M_b.min();
804 	  while (__y1 && __u >= __y1);
805 	  __sum = __s1 * __sum + (__s1 ? __u % __s1 : __u);
806 	}
807       return __sum;
808     }
809 
810 
811   template<typename _RandomNumberEngine, size_t __k>
812     constexpr size_t
813     shuffle_order_engine<_RandomNumberEngine, __k>::table_size;
814 
815   template<typename _RandomNumberEngine, size_t __k>
816     typename shuffle_order_engine<_RandomNumberEngine, __k>::result_type
817     shuffle_order_engine<_RandomNumberEngine, __k>::
operator ()()818     operator()()
819     {
820       size_t __j = __k * ((_M_y - _M_b.min())
821 			  / (_M_b.max() - _M_b.min() + 1.0L));
822       _M_y = _M_v[__j];
823       _M_v[__j] = _M_b();
824 
825       return _M_y;
826     }
827 
828   template<typename _RandomNumberEngine, size_t __k,
829 	   typename _CharT, typename _Traits>
830     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const shuffle_order_engine<_RandomNumberEngine,__k> & __x)831     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
832 	       const shuffle_order_engine<_RandomNumberEngine, __k>& __x)
833     {
834       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
835       typedef typename __ostream_type::ios_base    __ios_base;
836 
837       const typename __ios_base::fmtflags __flags = __os.flags();
838       const _CharT __fill = __os.fill();
839       const _CharT __space = __os.widen(' ');
840       __os.flags(__ios_base::dec | __ios_base::fixed | __ios_base::left);
841       __os.fill(__space);
842 
843       __os << __x.base();
844       for (size_t __i = 0; __i < __k; ++__i)
845 	__os << __space << __x._M_v[__i];
846       __os << __space << __x._M_y;
847 
848       __os.flags(__flags);
849       __os.fill(__fill);
850       return __os;
851     }
852 
853   template<typename _RandomNumberEngine, size_t __k,
854 	   typename _CharT, typename _Traits>
855     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,shuffle_order_engine<_RandomNumberEngine,__k> & __x)856     operator>>(std::basic_istream<_CharT, _Traits>& __is,
857 	       shuffle_order_engine<_RandomNumberEngine, __k>& __x)
858     {
859       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
860       typedef typename __istream_type::ios_base    __ios_base;
861 
862       const typename __ios_base::fmtflags __flags = __is.flags();
863       __is.flags(__ios_base::dec | __ios_base::skipws);
864 
865       __is >> __x._M_b;
866       for (size_t __i = 0; __i < __k; ++__i)
867 	__is >> __x._M_v[__i];
868       __is >> __x._M_y;
869 
870       __is.flags(__flags);
871       return __is;
872     }
873 
874 
875   template<typename _IntType, typename _CharT, typename _Traits>
876     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const uniform_int_distribution<_IntType> & __x)877     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
878 	       const uniform_int_distribution<_IntType>& __x)
879     {
880       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
881       typedef typename __ostream_type::ios_base    __ios_base;
882 
883       const typename __ios_base::fmtflags __flags = __os.flags();
884       const _CharT __fill = __os.fill();
885       const _CharT __space = __os.widen(' ');
886       __os.flags(__ios_base::scientific | __ios_base::left);
887       __os.fill(__space);
888 
889       __os << __x.a() << __space << __x.b();
890 
891       __os.flags(__flags);
892       __os.fill(__fill);
893       return __os;
894     }
895 
896   template<typename _IntType, typename _CharT, typename _Traits>
897     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,uniform_int_distribution<_IntType> & __x)898     operator>>(std::basic_istream<_CharT, _Traits>& __is,
899 	       uniform_int_distribution<_IntType>& __x)
900     {
901       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
902       typedef typename __istream_type::ios_base    __ios_base;
903 
904       const typename __ios_base::fmtflags __flags = __is.flags();
905       __is.flags(__ios_base::dec | __ios_base::skipws);
906 
907       _IntType __a, __b;
908       if (__is >> __a >> __b)
909 	__x.param(typename uniform_int_distribution<_IntType>::
910 		  param_type(__a, __b));
911 
912       __is.flags(__flags);
913       return __is;
914     }
915 
916 
917   template<typename _RealType>
918     template<typename _ForwardIterator,
919 	     typename _UniformRandomNumberGenerator>
920       void
921       uniform_real_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)922       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
923 		      _UniformRandomNumberGenerator& __urng,
924 		      const param_type& __p)
925       {
926 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
927 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
928 	  __aurng(__urng);
929 	auto __range = __p.b() - __p.a();
930 	while (__f != __t)
931 	  *__f++ = __aurng() * __range + __p.a();
932       }
933 
934   template<typename _RealType, typename _CharT, typename _Traits>
935     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const uniform_real_distribution<_RealType> & __x)936     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
937 	       const uniform_real_distribution<_RealType>& __x)
938     {
939       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
940       typedef typename __ostream_type::ios_base    __ios_base;
941 
942       const typename __ios_base::fmtflags __flags = __os.flags();
943       const _CharT __fill = __os.fill();
944       const std::streamsize __precision = __os.precision();
945       const _CharT __space = __os.widen(' ');
946       __os.flags(__ios_base::scientific | __ios_base::left);
947       __os.fill(__space);
948       __os.precision(std::numeric_limits<_RealType>::max_digits10);
949 
950       __os << __x.a() << __space << __x.b();
951 
952       __os.flags(__flags);
953       __os.fill(__fill);
954       __os.precision(__precision);
955       return __os;
956     }
957 
958   template<typename _RealType, typename _CharT, typename _Traits>
959     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,uniform_real_distribution<_RealType> & __x)960     operator>>(std::basic_istream<_CharT, _Traits>& __is,
961 	       uniform_real_distribution<_RealType>& __x)
962     {
963       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
964       typedef typename __istream_type::ios_base    __ios_base;
965 
966       const typename __ios_base::fmtflags __flags = __is.flags();
967       __is.flags(__ios_base::skipws);
968 
969       _RealType __a, __b;
970       if (__is >> __a >> __b)
971 	__x.param(typename uniform_real_distribution<_RealType>::
972 		  param_type(__a, __b));
973 
974       __is.flags(__flags);
975       return __is;
976     }
977 
978 
979   template<typename _ForwardIterator,
980 	   typename _UniformRandomNumberGenerator>
981     void
982     std::bernoulli_distribution::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)983     __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
984 		    _UniformRandomNumberGenerator& __urng,
985 		    const param_type& __p)
986     {
987       __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
988       __detail::_Adaptor<_UniformRandomNumberGenerator, double>
989 	__aurng(__urng);
990       auto __limit = __p.p() * (__aurng.max() - __aurng.min());
991 
992       while (__f != __t)
993 	*__f++ = (__aurng() - __aurng.min()) < __limit;
994     }
995 
996   template<typename _CharT, typename _Traits>
997     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const bernoulli_distribution & __x)998     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
999 	       const bernoulli_distribution& __x)
1000     {
1001       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
1002       typedef typename __ostream_type::ios_base    __ios_base;
1003 
1004       const typename __ios_base::fmtflags __flags = __os.flags();
1005       const _CharT __fill = __os.fill();
1006       const std::streamsize __precision = __os.precision();
1007       __os.flags(__ios_base::scientific | __ios_base::left);
1008       __os.fill(__os.widen(' '));
1009       __os.precision(std::numeric_limits<double>::max_digits10);
1010 
1011       __os << __x.p();
1012 
1013       __os.flags(__flags);
1014       __os.fill(__fill);
1015       __os.precision(__precision);
1016       return __os;
1017     }
1018 
1019 
1020   template<typename _IntType>
1021     template<typename _UniformRandomNumberGenerator>
1022       typename geometric_distribution<_IntType>::result_type
1023       geometric_distribution<_IntType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __param)1024       operator()(_UniformRandomNumberGenerator& __urng,
1025 		 const param_type& __param)
1026       {
1027 	// About the epsilon thing see this thread:
1028 	// http://gcc.gnu.org/ml/gcc-patches/2006-10/msg00971.html
1029 	const double __naf =
1030 	  (1 - std::numeric_limits<double>::epsilon()) / 2;
1031 	// The largest _RealType convertible to _IntType.
1032 	const double __thr =
1033 	  std::numeric_limits<_IntType>::max() + __naf;
1034 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
1035 	  __aurng(__urng);
1036 
1037 	double __cand;
1038 	do
1039 	  __cand = std::floor(std::log(1.0 - __aurng()) / __param._M_log_1_p);
1040 	while (__cand >= __thr);
1041 
1042 	return result_type(__cand + __naf);
1043       }
1044 
1045   template<typename _IntType>
1046     template<typename _ForwardIterator,
1047 	     typename _UniformRandomNumberGenerator>
1048       void
1049       geometric_distribution<_IntType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __param)1050       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
1051 		      _UniformRandomNumberGenerator& __urng,
1052 		      const param_type& __param)
1053       {
1054 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1055 	// About the epsilon thing see this thread:
1056 	// http://gcc.gnu.org/ml/gcc-patches/2006-10/msg00971.html
1057 	const double __naf =
1058 	  (1 - std::numeric_limits<double>::epsilon()) / 2;
1059 	// The largest _RealType convertible to _IntType.
1060 	const double __thr =
1061 	  std::numeric_limits<_IntType>::max() + __naf;
1062 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
1063 	  __aurng(__urng);
1064 
1065 	while (__f != __t)
1066 	  {
1067 	    double __cand;
1068 	    do
1069 	      __cand = std::floor(std::log(1.0 - __aurng())
1070 				  / __param._M_log_1_p);
1071 	    while (__cand >= __thr);
1072 
1073 	    *__f++ = __cand + __naf;
1074 	  }
1075       }
1076 
1077   template<typename _IntType,
1078 	   typename _CharT, typename _Traits>
1079     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const geometric_distribution<_IntType> & __x)1080     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1081 	       const geometric_distribution<_IntType>& __x)
1082     {
1083       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
1084       typedef typename __ostream_type::ios_base    __ios_base;
1085 
1086       const typename __ios_base::fmtflags __flags = __os.flags();
1087       const _CharT __fill = __os.fill();
1088       const std::streamsize __precision = __os.precision();
1089       __os.flags(__ios_base::scientific | __ios_base::left);
1090       __os.fill(__os.widen(' '));
1091       __os.precision(std::numeric_limits<double>::max_digits10);
1092 
1093       __os << __x.p();
1094 
1095       __os.flags(__flags);
1096       __os.fill(__fill);
1097       __os.precision(__precision);
1098       return __os;
1099     }
1100 
1101   template<typename _IntType,
1102 	   typename _CharT, typename _Traits>
1103     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,geometric_distribution<_IntType> & __x)1104     operator>>(std::basic_istream<_CharT, _Traits>& __is,
1105 	       geometric_distribution<_IntType>& __x)
1106     {
1107       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
1108       typedef typename __istream_type::ios_base    __ios_base;
1109 
1110       const typename __ios_base::fmtflags __flags = __is.flags();
1111       __is.flags(__ios_base::skipws);
1112 
1113       double __p;
1114       if (__is >> __p)
1115 	__x.param(typename geometric_distribution<_IntType>::param_type(__p));
1116 
1117       __is.flags(__flags);
1118       return __is;
1119     }
1120 
1121   // This is Leger's algorithm, also in Devroye, Ch. X, Example 1.5.
1122   template<typename _IntType>
1123     template<typename _UniformRandomNumberGenerator>
1124       typename negative_binomial_distribution<_IntType>::result_type
1125       negative_binomial_distribution<_IntType>::
operator ()(_UniformRandomNumberGenerator & __urng)1126       operator()(_UniformRandomNumberGenerator& __urng)
1127       {
1128 	const double __y = _M_gd(__urng);
1129 
1130 	// XXX Is the constructor too slow?
1131 	std::poisson_distribution<result_type> __poisson(__y);
1132 	return __poisson(__urng);
1133       }
1134 
1135   template<typename _IntType>
1136     template<typename _UniformRandomNumberGenerator>
1137       typename negative_binomial_distribution<_IntType>::result_type
1138       negative_binomial_distribution<_IntType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __p)1139       operator()(_UniformRandomNumberGenerator& __urng,
1140 		 const param_type& __p)
1141       {
1142 	typedef typename std::gamma_distribution<double>::param_type
1143 	  param_type;
1144 
1145 	const double __y =
1146 	  _M_gd(__urng, param_type(__p.k(), (1.0 - __p.p()) / __p.p()));
1147 
1148 	std::poisson_distribution<result_type> __poisson(__y);
1149 	return __poisson(__urng);
1150       }
1151 
1152   template<typename _IntType>
1153     template<typename _ForwardIterator,
1154 	     typename _UniformRandomNumberGenerator>
1155       void
1156       negative_binomial_distribution<_IntType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng)1157       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
1158 		      _UniformRandomNumberGenerator& __urng)
1159       {
1160 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1161 	while (__f != __t)
1162 	  {
1163 	    const double __y = _M_gd(__urng);
1164 
1165 	    // XXX Is the constructor too slow?
1166 	    std::poisson_distribution<result_type> __poisson(__y);
1167 	    *__f++ = __poisson(__urng);
1168 	  }
1169       }
1170 
1171   template<typename _IntType>
1172     template<typename _ForwardIterator,
1173 	     typename _UniformRandomNumberGenerator>
1174       void
1175       negative_binomial_distribution<_IntType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)1176       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
1177 		      _UniformRandomNumberGenerator& __urng,
1178 		      const param_type& __p)
1179       {
1180 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1181 	typename std::gamma_distribution<result_type>::param_type
1182 	  __p2(__p.k(), (1.0 - __p.p()) / __p.p());
1183 
1184 	while (__f != __t)
1185 	  {
1186 	    const double __y = _M_gd(__urng, __p2);
1187 
1188 	    std::poisson_distribution<result_type> __poisson(__y);
1189 	    *__f++ = __poisson(__urng);
1190 	  }
1191       }
1192 
1193   template<typename _IntType, typename _CharT, typename _Traits>
1194     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const negative_binomial_distribution<_IntType> & __x)1195     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1196 	       const negative_binomial_distribution<_IntType>& __x)
1197     {
1198       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
1199       typedef typename __ostream_type::ios_base    __ios_base;
1200 
1201       const typename __ios_base::fmtflags __flags = __os.flags();
1202       const _CharT __fill = __os.fill();
1203       const std::streamsize __precision = __os.precision();
1204       const _CharT __space = __os.widen(' ');
1205       __os.flags(__ios_base::scientific | __ios_base::left);
1206       __os.fill(__os.widen(' '));
1207       __os.precision(std::numeric_limits<double>::max_digits10);
1208 
1209       __os << __x.k() << __space << __x.p()
1210 	   << __space << __x._M_gd;
1211 
1212       __os.flags(__flags);
1213       __os.fill(__fill);
1214       __os.precision(__precision);
1215       return __os;
1216     }
1217 
1218   template<typename _IntType, typename _CharT, typename _Traits>
1219     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,negative_binomial_distribution<_IntType> & __x)1220     operator>>(std::basic_istream<_CharT, _Traits>& __is,
1221 	       negative_binomial_distribution<_IntType>& __x)
1222     {
1223       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
1224       typedef typename __istream_type::ios_base    __ios_base;
1225 
1226       const typename __ios_base::fmtflags __flags = __is.flags();
1227       __is.flags(__ios_base::skipws);
1228 
1229       _IntType __k;
1230       double __p;
1231       if (__is >> __k >> __p >> __x._M_gd)
1232 	__x.param(typename negative_binomial_distribution<_IntType>::
1233 		  param_type(__k, __p));
1234 
1235       __is.flags(__flags);
1236       return __is;
1237     }
1238 
1239 
1240   template<typename _IntType>
1241     void
1242     poisson_distribution<_IntType>::param_type::
_M_initialize()1243     _M_initialize()
1244     {
1245 #if _GLIBCXX_USE_C99_MATH_TR1
1246       if (_M_mean >= 12)
1247 	{
1248 	  const double __m = std::floor(_M_mean);
1249 	  _M_lm_thr = std::log(_M_mean);
1250 	  _M_lfm = std::lgamma(__m + 1);
1251 	  _M_sm = std::sqrt(__m);
1252 
1253 	  const double __pi_4 = 0.7853981633974483096156608458198757L;
1254 	  const double __dx = std::sqrt(2 * __m * std::log(32 * __m
1255 							      / __pi_4));
1256 	  _M_d = std::round(std::max<double>(6.0, std::min(__m, __dx)));
1257 	  const double __cx = 2 * __m + _M_d;
1258 	  _M_scx = std::sqrt(__cx / 2);
1259 	  _M_1cx = 1 / __cx;
1260 
1261 	  _M_c2b = std::sqrt(__pi_4 * __cx) * std::exp(_M_1cx);
1262 	  _M_cb = 2 * __cx * std::exp(-_M_d * _M_1cx * (1 + _M_d / 2))
1263 		/ _M_d;
1264 	}
1265       else
1266 #endif
1267 	_M_lm_thr = std::exp(-_M_mean);
1268       }
1269 
1270   /**
1271    * A rejection algorithm when mean >= 12 and a simple method based
1272    * upon the multiplication of uniform random variates otherwise.
1273    * NB: The former is available only if _GLIBCXX_USE_C99_MATH_TR1
1274    * is defined.
1275    *
1276    * Reference:
1277    * Devroye, L. Non-Uniform Random Variates Generation. Springer-Verlag,
1278    * New York, 1986, Ch. X, Sects. 3.3 & 3.4 (+ Errata!).
1279    */
1280   template<typename _IntType>
1281     template<typename _UniformRandomNumberGenerator>
1282       typename poisson_distribution<_IntType>::result_type
1283       poisson_distribution<_IntType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __param)1284       operator()(_UniformRandomNumberGenerator& __urng,
1285 		 const param_type& __param)
1286       {
1287 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
1288 	  __aurng(__urng);
1289 #if _GLIBCXX_USE_C99_MATH_TR1
1290 	if (__param.mean() >= 12)
1291 	  {
1292 	    double __x;
1293 
1294 	    // See comments above...
1295 	    const double __naf =
1296 	      (1 - std::numeric_limits<double>::epsilon()) / 2;
1297 	    const double __thr =
1298 	      std::numeric_limits<_IntType>::max() + __naf;
1299 
1300 	    const double __m = std::floor(__param.mean());
1301 	    // sqrt(pi / 2)
1302 	    const double __spi_2 = 1.2533141373155002512078826424055226L;
1303 	    const double __c1 = __param._M_sm * __spi_2;
1304 	    const double __c2 = __param._M_c2b + __c1;
1305 	    const double __c3 = __c2 + 1;
1306 	    const double __c4 = __c3 + 1;
1307 	    // 1 / 78
1308 	    const double __178 = 0.0128205128205128205128205128205128L;
1309 	    // e^(1 / 78)
1310 	    const double __e178 = 1.0129030479320018583185514777512983L;
1311 	    const double __c5 = __c4 + __e178;
1312 	    const double __c = __param._M_cb + __c5;
1313 	    const double __2cx = 2 * (2 * __m + __param._M_d);
1314 
1315 	    bool __reject = true;
1316 	    do
1317 	      {
1318 		const double __u = __c * __aurng();
1319 		const double __e = -std::log(1.0 - __aurng());
1320 
1321 		double __w = 0.0;
1322 
1323 		if (__u <= __c1)
1324 		  {
1325 		    const double __n = _M_nd(__urng);
1326 		    const double __y = -std::abs(__n) * __param._M_sm - 1;
1327 		    __x = std::floor(__y);
1328 		    __w = -__n * __n / 2;
1329 		    if (__x < -__m)
1330 		      continue;
1331 		  }
1332 		else if (__u <= __c2)
1333 		  {
1334 		    const double __n = _M_nd(__urng);
1335 		    const double __y = 1 + std::abs(__n) * __param._M_scx;
1336 		    __x = std::ceil(__y);
1337 		    __w = __y * (2 - __y) * __param._M_1cx;
1338 		    if (__x > __param._M_d)
1339 		      continue;
1340 		  }
1341 		else if (__u <= __c3)
1342 		  // NB: This case not in the book, nor in the Errata,
1343 		  // but should be ok...
1344 		  __x = -1;
1345 		else if (__u <= __c4)
1346 		  __x = 0;
1347 		else if (__u <= __c5)
1348 		  {
1349 		    __x = 1;
1350 		    // Only in the Errata, see libstdc++/83237.
1351 		    __w = __178;
1352 		  }
1353 		else
1354 		  {
1355 		    const double __v = -std::log(1.0 - __aurng());
1356 		    const double __y = __param._M_d
1357 				     + __v * __2cx / __param._M_d;
1358 		    __x = std::ceil(__y);
1359 		    __w = -__param._M_d * __param._M_1cx * (1 + __y / 2);
1360 		  }
1361 
1362 		__reject = (__w - __e - __x * __param._M_lm_thr
1363 			    > __param._M_lfm - std::lgamma(__x + __m + 1));
1364 
1365 		__reject |= __x + __m >= __thr;
1366 
1367 	      } while (__reject);
1368 
1369 	    return result_type(__x + __m + __naf);
1370 	  }
1371 	else
1372 #endif
1373 	  {
1374 	    _IntType     __x = 0;
1375 	    double __prod = 1.0;
1376 
1377 	    do
1378 	      {
1379 		__prod *= __aurng();
1380 		__x += 1;
1381 	      }
1382 	    while (__prod > __param._M_lm_thr);
1383 
1384 	    return __x - 1;
1385 	  }
1386       }
1387 
1388   template<typename _IntType>
1389     template<typename _ForwardIterator,
1390 	     typename _UniformRandomNumberGenerator>
1391       void
1392       poisson_distribution<_IntType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __param)1393       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
1394 		      _UniformRandomNumberGenerator& __urng,
1395 		      const param_type& __param)
1396       {
1397 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1398 	// We could duplicate everything from operator()...
1399 	while (__f != __t)
1400 	  *__f++ = this->operator()(__urng, __param);
1401       }
1402 
1403   template<typename _IntType,
1404 	   typename _CharT, typename _Traits>
1405     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const poisson_distribution<_IntType> & __x)1406     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1407 	       const poisson_distribution<_IntType>& __x)
1408     {
1409       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
1410       typedef typename __ostream_type::ios_base    __ios_base;
1411 
1412       const typename __ios_base::fmtflags __flags = __os.flags();
1413       const _CharT __fill = __os.fill();
1414       const std::streamsize __precision = __os.precision();
1415       const _CharT __space = __os.widen(' ');
1416       __os.flags(__ios_base::scientific | __ios_base::left);
1417       __os.fill(__space);
1418       __os.precision(std::numeric_limits<double>::max_digits10);
1419 
1420       __os << __x.mean() << __space << __x._M_nd;
1421 
1422       __os.flags(__flags);
1423       __os.fill(__fill);
1424       __os.precision(__precision);
1425       return __os;
1426     }
1427 
1428   template<typename _IntType,
1429 	   typename _CharT, typename _Traits>
1430     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,poisson_distribution<_IntType> & __x)1431     operator>>(std::basic_istream<_CharT, _Traits>& __is,
1432 	       poisson_distribution<_IntType>& __x)
1433     {
1434       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
1435       typedef typename __istream_type::ios_base    __ios_base;
1436 
1437       const typename __ios_base::fmtflags __flags = __is.flags();
1438       __is.flags(__ios_base::skipws);
1439 
1440       double __mean;
1441       if (__is >> __mean >> __x._M_nd)
1442 	__x.param(typename poisson_distribution<_IntType>::param_type(__mean));
1443 
1444       __is.flags(__flags);
1445       return __is;
1446     }
1447 
1448 
1449   template<typename _IntType>
1450     void
1451     binomial_distribution<_IntType>::param_type::
_M_initialize()1452     _M_initialize()
1453     {
1454       const double __p12 = _M_p <= 0.5 ? _M_p : 1.0 - _M_p;
1455 
1456       _M_easy = true;
1457 
1458 #if _GLIBCXX_USE_C99_MATH_TR1
1459       if (_M_t * __p12 >= 8)
1460 	{
1461 	  _M_easy = false;
1462 	  const double __np = std::floor(_M_t * __p12);
1463 	  const double __pa = __np / _M_t;
1464 	  const double __1p = 1 - __pa;
1465 
1466 	  const double __pi_4 = 0.7853981633974483096156608458198757L;
1467 	  const double __d1x =
1468 	    std::sqrt(__np * __1p * std::log(32 * __np
1469 					     / (81 * __pi_4 * __1p)));
1470 	  _M_d1 = std::round(std::max<double>(1.0, __d1x));
1471 	  const double __d2x =
1472 	    std::sqrt(__np * __1p * std::log(32 * _M_t * __1p
1473 					     / (__pi_4 * __pa)));
1474 	  _M_d2 = std::round(std::max<double>(1.0, __d2x));
1475 
1476 	  // sqrt(pi / 2)
1477 	  const double __spi_2 = 1.2533141373155002512078826424055226L;
1478 	  _M_s1 = std::sqrt(__np * __1p) * (1 + _M_d1 / (4 * __np));
1479 	  _M_s2 = std::sqrt(__np * __1p) * (1 + _M_d2 / (4 * _M_t * __1p));
1480 	  _M_c = 2 * _M_d1 / __np;
1481 	  _M_a1 = std::exp(_M_c) * _M_s1 * __spi_2;
1482 	  const double __a12 = _M_a1 + _M_s2 * __spi_2;
1483 	  const double __s1s = _M_s1 * _M_s1;
1484 	  _M_a123 = __a12 + (std::exp(_M_d1 / (_M_t * __1p))
1485 			     * 2 * __s1s / _M_d1
1486 			     * std::exp(-_M_d1 * _M_d1 / (2 * __s1s)));
1487 	  const double __s2s = _M_s2 * _M_s2;
1488 	  _M_s = (_M_a123 + 2 * __s2s / _M_d2
1489 		  * std::exp(-_M_d2 * _M_d2 / (2 * __s2s)));
1490 	  _M_lf = (std::lgamma(__np + 1)
1491 		   + std::lgamma(_M_t - __np + 1));
1492 	  _M_lp1p = std::log(__pa / __1p);
1493 
1494 	  _M_q = -std::log(1 - (__p12 - __pa) / __1p);
1495 	}
1496       else
1497 #endif
1498 	_M_q = -std::log(1 - __p12);
1499     }
1500 
1501   template<typename _IntType>
1502     template<typename _UniformRandomNumberGenerator>
1503       typename binomial_distribution<_IntType>::result_type
1504       binomial_distribution<_IntType>::
_M_waiting(_UniformRandomNumberGenerator & __urng,_IntType __t,double __q)1505       _M_waiting(_UniformRandomNumberGenerator& __urng,
1506 		 _IntType __t, double __q)
1507       {
1508 	_IntType __x = 0;
1509 	double __sum = 0.0;
1510 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
1511 	  __aurng(__urng);
1512 
1513 	do
1514 	  {
1515 	    if (__t == __x)
1516 	      return __x;
1517 	    const double __e = -std::log(1.0 - __aurng());
1518 	    __sum += __e / (__t - __x);
1519 	    __x += 1;
1520 	  }
1521 	while (__sum <= __q);
1522 
1523 	return __x - 1;
1524       }
1525 
1526   /**
1527    * A rejection algorithm when t * p >= 8 and a simple waiting time
1528    * method - the second in the referenced book - otherwise.
1529    * NB: The former is available only if _GLIBCXX_USE_C99_MATH_TR1
1530    * is defined.
1531    *
1532    * Reference:
1533    * Devroye, L. Non-Uniform Random Variates Generation. Springer-Verlag,
1534    * New York, 1986, Ch. X, Sect. 4 (+ Errata!).
1535    */
1536   template<typename _IntType>
1537     template<typename _UniformRandomNumberGenerator>
1538       typename binomial_distribution<_IntType>::result_type
1539       binomial_distribution<_IntType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __param)1540       operator()(_UniformRandomNumberGenerator& __urng,
1541 		 const param_type& __param)
1542       {
1543 	result_type __ret;
1544 	const _IntType __t = __param.t();
1545 	const double __p = __param.p();
1546 	const double __p12 = __p <= 0.5 ? __p : 1.0 - __p;
1547 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
1548 	  __aurng(__urng);
1549 
1550 #if _GLIBCXX_USE_C99_MATH_TR1
1551 	if (!__param._M_easy)
1552 	  {
1553 	    double __x;
1554 
1555 	    // See comments above...
1556 	    const double __naf =
1557 	      (1 - std::numeric_limits<double>::epsilon()) / 2;
1558 	    const double __thr =
1559 	      std::numeric_limits<_IntType>::max() + __naf;
1560 
1561 	    const double __np = std::floor(__t * __p12);
1562 
1563 	    // sqrt(pi / 2)
1564 	    const double __spi_2 = 1.2533141373155002512078826424055226L;
1565 	    const double __a1 = __param._M_a1;
1566 	    const double __a12 = __a1 + __param._M_s2 * __spi_2;
1567 	    const double __a123 = __param._M_a123;
1568 	    const double __s1s = __param._M_s1 * __param._M_s1;
1569 	    const double __s2s = __param._M_s2 * __param._M_s2;
1570 
1571 	    bool __reject;
1572 	    do
1573 	      {
1574 		const double __u = __param._M_s * __aurng();
1575 
1576 		double __v;
1577 
1578 		if (__u <= __a1)
1579 		  {
1580 		    const double __n = _M_nd(__urng);
1581 		    const double __y = __param._M_s1 * std::abs(__n);
1582 		    __reject = __y >= __param._M_d1;
1583 		    if (!__reject)
1584 		      {
1585 			const double __e = -std::log(1.0 - __aurng());
1586 			__x = std::floor(__y);
1587 			__v = -__e - __n * __n / 2 + __param._M_c;
1588 		      }
1589 		  }
1590 		else if (__u <= __a12)
1591 		  {
1592 		    const double __n = _M_nd(__urng);
1593 		    const double __y = __param._M_s2 * std::abs(__n);
1594 		    __reject = __y >= __param._M_d2;
1595 		    if (!__reject)
1596 		      {
1597 			const double __e = -std::log(1.0 - __aurng());
1598 			__x = std::floor(-__y);
1599 			__v = -__e - __n * __n / 2;
1600 		      }
1601 		  }
1602 		else if (__u <= __a123)
1603 		  {
1604 		    const double __e1 = -std::log(1.0 - __aurng());
1605 		    const double __e2 = -std::log(1.0 - __aurng());
1606 
1607 		    const double __y = __param._M_d1
1608 				     + 2 * __s1s * __e1 / __param._M_d1;
1609 		    __x = std::floor(__y);
1610 		    __v = (-__e2 + __param._M_d1 * (1 / (__t - __np)
1611 						    -__y / (2 * __s1s)));
1612 		    __reject = false;
1613 		  }
1614 		else
1615 		  {
1616 		    const double __e1 = -std::log(1.0 - __aurng());
1617 		    const double __e2 = -std::log(1.0 - __aurng());
1618 
1619 		    const double __y = __param._M_d2
1620 				     + 2 * __s2s * __e1 / __param._M_d2;
1621 		    __x = std::floor(-__y);
1622 		    __v = -__e2 - __param._M_d2 * __y / (2 * __s2s);
1623 		    __reject = false;
1624 		  }
1625 
1626 		__reject = __reject || __x < -__np || __x > __t - __np;
1627 		if (!__reject)
1628 		  {
1629 		    const double __lfx =
1630 		      std::lgamma(__np + __x + 1)
1631 		      + std::lgamma(__t - (__np + __x) + 1);
1632 		    __reject = __v > __param._M_lf - __lfx
1633 			     + __x * __param._M_lp1p;
1634 		  }
1635 
1636 		__reject |= __x + __np >= __thr;
1637 	      }
1638 	    while (__reject);
1639 
1640 	    __x += __np + __naf;
1641 
1642 	    const _IntType __z = _M_waiting(__urng, __t - _IntType(__x),
1643 					    __param._M_q);
1644 	    __ret = _IntType(__x) + __z;
1645 	  }
1646 	else
1647 #endif
1648 	  __ret = _M_waiting(__urng, __t, __param._M_q);
1649 
1650 	if (__p12 != __p)
1651 	  __ret = __t - __ret;
1652 	return __ret;
1653       }
1654 
1655   template<typename _IntType>
1656     template<typename _ForwardIterator,
1657 	     typename _UniformRandomNumberGenerator>
1658       void
1659       binomial_distribution<_IntType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __param)1660       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
1661 		      _UniformRandomNumberGenerator& __urng,
1662 		      const param_type& __param)
1663       {
1664 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1665 	// We could duplicate everything from operator()...
1666 	while (__f != __t)
1667 	  *__f++ = this->operator()(__urng, __param);
1668       }
1669 
1670   template<typename _IntType,
1671 	   typename _CharT, typename _Traits>
1672     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const binomial_distribution<_IntType> & __x)1673     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1674 	       const binomial_distribution<_IntType>& __x)
1675     {
1676       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
1677       typedef typename __ostream_type::ios_base    __ios_base;
1678 
1679       const typename __ios_base::fmtflags __flags = __os.flags();
1680       const _CharT __fill = __os.fill();
1681       const std::streamsize __precision = __os.precision();
1682       const _CharT __space = __os.widen(' ');
1683       __os.flags(__ios_base::scientific | __ios_base::left);
1684       __os.fill(__space);
1685       __os.precision(std::numeric_limits<double>::max_digits10);
1686 
1687       __os << __x.t() << __space << __x.p()
1688 	   << __space << __x._M_nd;
1689 
1690       __os.flags(__flags);
1691       __os.fill(__fill);
1692       __os.precision(__precision);
1693       return __os;
1694     }
1695 
1696   template<typename _IntType,
1697 	   typename _CharT, typename _Traits>
1698     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,binomial_distribution<_IntType> & __x)1699     operator>>(std::basic_istream<_CharT, _Traits>& __is,
1700 	       binomial_distribution<_IntType>& __x)
1701     {
1702       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
1703       typedef typename __istream_type::ios_base    __ios_base;
1704 
1705       const typename __ios_base::fmtflags __flags = __is.flags();
1706       __is.flags(__ios_base::dec | __ios_base::skipws);
1707 
1708       _IntType __t;
1709       double __p;
1710       if (__is >> __t >> __p >> __x._M_nd)
1711 	__x.param(typename binomial_distribution<_IntType>::
1712 		  param_type(__t, __p));
1713 
1714       __is.flags(__flags);
1715       return __is;
1716     }
1717 
1718 
1719   template<typename _RealType>
1720     template<typename _ForwardIterator,
1721 	     typename _UniformRandomNumberGenerator>
1722       void
1723       std::exponential_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)1724       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
1725 		      _UniformRandomNumberGenerator& __urng,
1726 		      const param_type& __p)
1727       {
1728 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1729 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
1730 	  __aurng(__urng);
1731 	while (__f != __t)
1732 	  *__f++ = -std::log(result_type(1) - __aurng()) / __p.lambda();
1733       }
1734 
1735   template<typename _RealType, typename _CharT, typename _Traits>
1736     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const exponential_distribution<_RealType> & __x)1737     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1738 	       const exponential_distribution<_RealType>& __x)
1739     {
1740       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
1741       typedef typename __ostream_type::ios_base    __ios_base;
1742 
1743       const typename __ios_base::fmtflags __flags = __os.flags();
1744       const _CharT __fill = __os.fill();
1745       const std::streamsize __precision = __os.precision();
1746       __os.flags(__ios_base::scientific | __ios_base::left);
1747       __os.fill(__os.widen(' '));
1748       __os.precision(std::numeric_limits<_RealType>::max_digits10);
1749 
1750       __os << __x.lambda();
1751 
1752       __os.flags(__flags);
1753       __os.fill(__fill);
1754       __os.precision(__precision);
1755       return __os;
1756     }
1757 
1758   template<typename _RealType, typename _CharT, typename _Traits>
1759     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,exponential_distribution<_RealType> & __x)1760     operator>>(std::basic_istream<_CharT, _Traits>& __is,
1761 	       exponential_distribution<_RealType>& __x)
1762     {
1763       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
1764       typedef typename __istream_type::ios_base    __ios_base;
1765 
1766       const typename __ios_base::fmtflags __flags = __is.flags();
1767       __is.flags(__ios_base::dec | __ios_base::skipws);
1768 
1769       _RealType __lambda;
1770       if (__is >> __lambda)
1771 	__x.param(typename exponential_distribution<_RealType>::
1772 		  param_type(__lambda));
1773 
1774       __is.flags(__flags);
1775       return __is;
1776     }
1777 
1778 
1779   /**
1780    * Polar method due to Marsaglia.
1781    *
1782    * Devroye, L. Non-Uniform Random Variates Generation. Springer-Verlag,
1783    * New York, 1986, Ch. V, Sect. 4.4.
1784    */
1785   template<typename _RealType>
1786     template<typename _UniformRandomNumberGenerator>
1787       typename normal_distribution<_RealType>::result_type
1788       normal_distribution<_RealType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __param)1789       operator()(_UniformRandomNumberGenerator& __urng,
1790 		 const param_type& __param)
1791       {
1792 	result_type __ret;
1793 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
1794 	  __aurng(__urng);
1795 
1796 	if (_M_saved_available)
1797 	  {
1798 	    _M_saved_available = false;
1799 	    __ret = _M_saved;
1800 	  }
1801 	else
1802 	  {
1803 	    result_type __x, __y, __r2;
1804 	    do
1805 	      {
1806 		__x = result_type(2.0) * __aurng() - 1.0;
1807 		__y = result_type(2.0) * __aurng() - 1.0;
1808 		__r2 = __x * __x + __y * __y;
1809 	      }
1810 	    while (__r2 > 1.0 || __r2 == 0.0);
1811 
1812 	    const result_type __mult = std::sqrt(-2 * std::log(__r2) / __r2);
1813 	    _M_saved = __x * __mult;
1814 	    _M_saved_available = true;
1815 	    __ret = __y * __mult;
1816 	  }
1817 
1818 	__ret = __ret * __param.stddev() + __param.mean();
1819 	return __ret;
1820       }
1821 
1822   template<typename _RealType>
1823     template<typename _ForwardIterator,
1824 	     typename _UniformRandomNumberGenerator>
1825       void
1826       normal_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __param)1827       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
1828 		      _UniformRandomNumberGenerator& __urng,
1829 		      const param_type& __param)
1830       {
1831 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1832 
1833 	if (__f == __t)
1834 	  return;
1835 
1836 	if (_M_saved_available)
1837 	  {
1838 	    _M_saved_available = false;
1839 	    *__f++ = _M_saved * __param.stddev() + __param.mean();
1840 
1841 	    if (__f == __t)
1842 	      return;
1843 	  }
1844 
1845 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
1846 	  __aurng(__urng);
1847 
1848 	while (__f + 1 < __t)
1849 	  {
1850 	    result_type __x, __y, __r2;
1851 	    do
1852 	      {
1853 		__x = result_type(2.0) * __aurng() - 1.0;
1854 		__y = result_type(2.0) * __aurng() - 1.0;
1855 		__r2 = __x * __x + __y * __y;
1856 	      }
1857 	    while (__r2 > 1.0 || __r2 == 0.0);
1858 
1859 	    const result_type __mult = std::sqrt(-2 * std::log(__r2) / __r2);
1860 	    *__f++ = __y * __mult * __param.stddev() + __param.mean();
1861 	    *__f++ = __x * __mult * __param.stddev() + __param.mean();
1862 	  }
1863 
1864 	if (__f != __t)
1865 	  {
1866 	    result_type __x, __y, __r2;
1867 	    do
1868 	      {
1869 		__x = result_type(2.0) * __aurng() - 1.0;
1870 		__y = result_type(2.0) * __aurng() - 1.0;
1871 		__r2 = __x * __x + __y * __y;
1872 	      }
1873 	    while (__r2 > 1.0 || __r2 == 0.0);
1874 
1875 	    const result_type __mult = std::sqrt(-2 * std::log(__r2) / __r2);
1876 	    _M_saved = __x * __mult;
1877 	    _M_saved_available = true;
1878 	    *__f = __y * __mult * __param.stddev() + __param.mean();
1879 	  }
1880       }
1881 
1882   template<typename _RealType>
1883     bool
operator ==(const std::normal_distribution<_RealType> & __d1,const std::normal_distribution<_RealType> & __d2)1884     operator==(const std::normal_distribution<_RealType>& __d1,
1885 	       const std::normal_distribution<_RealType>& __d2)
1886     {
1887       if (__d1._M_param == __d2._M_param
1888 	  && __d1._M_saved_available == __d2._M_saved_available)
1889 	{
1890 	  if (__d1._M_saved_available
1891 	      && __d1._M_saved == __d2._M_saved)
1892 	    return true;
1893 	  else if(!__d1._M_saved_available)
1894 	    return true;
1895 	  else
1896 	    return false;
1897 	}
1898       else
1899 	return false;
1900     }
1901 
1902   template<typename _RealType, typename _CharT, typename _Traits>
1903     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const normal_distribution<_RealType> & __x)1904     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1905 	       const normal_distribution<_RealType>& __x)
1906     {
1907       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
1908       typedef typename __ostream_type::ios_base    __ios_base;
1909 
1910       const typename __ios_base::fmtflags __flags = __os.flags();
1911       const _CharT __fill = __os.fill();
1912       const std::streamsize __precision = __os.precision();
1913       const _CharT __space = __os.widen(' ');
1914       __os.flags(__ios_base::scientific | __ios_base::left);
1915       __os.fill(__space);
1916       __os.precision(std::numeric_limits<_RealType>::max_digits10);
1917 
1918       __os << __x.mean() << __space << __x.stddev()
1919 	   << __space << __x._M_saved_available;
1920       if (__x._M_saved_available)
1921 	__os << __space << __x._M_saved;
1922 
1923       __os.flags(__flags);
1924       __os.fill(__fill);
1925       __os.precision(__precision);
1926       return __os;
1927     }
1928 
1929   template<typename _RealType, typename _CharT, typename _Traits>
1930     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,normal_distribution<_RealType> & __x)1931     operator>>(std::basic_istream<_CharT, _Traits>& __is,
1932 	       normal_distribution<_RealType>& __x)
1933     {
1934       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
1935       typedef typename __istream_type::ios_base    __ios_base;
1936 
1937       const typename __ios_base::fmtflags __flags = __is.flags();
1938       __is.flags(__ios_base::dec | __ios_base::skipws);
1939 
1940       double __mean, __stddev;
1941       bool __saved_avail;
1942       if (__is >> __mean >> __stddev >> __saved_avail)
1943 	{
1944 	  if (__saved_avail && (__is >> __x._M_saved))
1945 	    {
1946 	      __x._M_saved_available = __saved_avail;
1947 	      __x.param(typename normal_distribution<_RealType>::
1948 			param_type(__mean, __stddev));
1949 	    }
1950 	}
1951 
1952       __is.flags(__flags);
1953       return __is;
1954     }
1955 
1956 
1957   template<typename _RealType>
1958     template<typename _ForwardIterator,
1959 	     typename _UniformRandomNumberGenerator>
1960       void
1961       lognormal_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)1962       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
1963 		      _UniformRandomNumberGenerator& __urng,
1964 		      const param_type& __p)
1965       {
1966 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1967 	  while (__f != __t)
1968 	    *__f++ = std::exp(__p.s() * _M_nd(__urng) + __p.m());
1969       }
1970 
1971   template<typename _RealType, typename _CharT, typename _Traits>
1972     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const lognormal_distribution<_RealType> & __x)1973     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1974 	       const lognormal_distribution<_RealType>& __x)
1975     {
1976       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
1977       typedef typename __ostream_type::ios_base    __ios_base;
1978 
1979       const typename __ios_base::fmtflags __flags = __os.flags();
1980       const _CharT __fill = __os.fill();
1981       const std::streamsize __precision = __os.precision();
1982       const _CharT __space = __os.widen(' ');
1983       __os.flags(__ios_base::scientific | __ios_base::left);
1984       __os.fill(__space);
1985       __os.precision(std::numeric_limits<_RealType>::max_digits10);
1986 
1987       __os << __x.m() << __space << __x.s()
1988 	   << __space << __x._M_nd;
1989 
1990       __os.flags(__flags);
1991       __os.fill(__fill);
1992       __os.precision(__precision);
1993       return __os;
1994     }
1995 
1996   template<typename _RealType, typename _CharT, typename _Traits>
1997     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,lognormal_distribution<_RealType> & __x)1998     operator>>(std::basic_istream<_CharT, _Traits>& __is,
1999 	       lognormal_distribution<_RealType>& __x)
2000     {
2001       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2002       typedef typename __istream_type::ios_base    __ios_base;
2003 
2004       const typename __ios_base::fmtflags __flags = __is.flags();
2005       __is.flags(__ios_base::dec | __ios_base::skipws);
2006 
2007       _RealType __m, __s;
2008       if (__is >> __m >> __s >> __x._M_nd)
2009 	__x.param(typename lognormal_distribution<_RealType>::
2010 		  param_type(__m, __s));
2011 
2012       __is.flags(__flags);
2013       return __is;
2014     }
2015 
2016   template<typename _RealType>
2017     template<typename _ForwardIterator,
2018 	     typename _UniformRandomNumberGenerator>
2019       void
2020       std::chi_squared_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng)2021       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2022 		      _UniformRandomNumberGenerator& __urng)
2023       {
2024 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2025 	while (__f != __t)
2026 	  *__f++ = 2 * _M_gd(__urng);
2027       }
2028 
2029   template<typename _RealType>
2030     template<typename _ForwardIterator,
2031 	     typename _UniformRandomNumberGenerator>
2032       void
2033       std::chi_squared_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const typename std::gamma_distribution<result_type>::param_type & __p)2034       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2035 		      _UniformRandomNumberGenerator& __urng,
2036 		      const typename
2037 		      std::gamma_distribution<result_type>::param_type& __p)
2038       {
2039 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2040 	while (__f != __t)
2041 	  *__f++ = 2 * _M_gd(__urng, __p);
2042       }
2043 
2044   template<typename _RealType, typename _CharT, typename _Traits>
2045     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const chi_squared_distribution<_RealType> & __x)2046     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2047 	       const chi_squared_distribution<_RealType>& __x)
2048     {
2049       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2050       typedef typename __ostream_type::ios_base    __ios_base;
2051 
2052       const typename __ios_base::fmtflags __flags = __os.flags();
2053       const _CharT __fill = __os.fill();
2054       const std::streamsize __precision = __os.precision();
2055       const _CharT __space = __os.widen(' ');
2056       __os.flags(__ios_base::scientific | __ios_base::left);
2057       __os.fill(__space);
2058       __os.precision(std::numeric_limits<_RealType>::max_digits10);
2059 
2060       __os << __x.n() << __space << __x._M_gd;
2061 
2062       __os.flags(__flags);
2063       __os.fill(__fill);
2064       __os.precision(__precision);
2065       return __os;
2066     }
2067 
2068   template<typename _RealType, typename _CharT, typename _Traits>
2069     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,chi_squared_distribution<_RealType> & __x)2070     operator>>(std::basic_istream<_CharT, _Traits>& __is,
2071 	       chi_squared_distribution<_RealType>& __x)
2072     {
2073       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2074       typedef typename __istream_type::ios_base    __ios_base;
2075 
2076       const typename __ios_base::fmtflags __flags = __is.flags();
2077       __is.flags(__ios_base::dec | __ios_base::skipws);
2078 
2079       _RealType __n;
2080       if (__is >> __n >> __x._M_gd)
2081 	__x.param(typename chi_squared_distribution<_RealType>::
2082 		  param_type(__n));
2083 
2084       __is.flags(__flags);
2085       return __is;
2086     }
2087 
2088 
2089   template<typename _RealType>
2090     template<typename _UniformRandomNumberGenerator>
2091       typename cauchy_distribution<_RealType>::result_type
2092       cauchy_distribution<_RealType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __p)2093       operator()(_UniformRandomNumberGenerator& __urng,
2094 		 const param_type& __p)
2095       {
2096 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
2097 	  __aurng(__urng);
2098 	_RealType __u;
2099 	do
2100 	  __u = __aurng();
2101 	while (__u == 0.5);
2102 
2103 	const _RealType __pi = 3.1415926535897932384626433832795029L;
2104 	return __p.a() + __p.b() * std::tan(__pi * __u);
2105       }
2106 
2107   template<typename _RealType>
2108     template<typename _ForwardIterator,
2109 	     typename _UniformRandomNumberGenerator>
2110       void
2111       cauchy_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)2112       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2113 		      _UniformRandomNumberGenerator& __urng,
2114 		      const param_type& __p)
2115       {
2116 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2117 	const _RealType __pi = 3.1415926535897932384626433832795029L;
2118 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
2119 	  __aurng(__urng);
2120 	while (__f != __t)
2121 	  {
2122 	    _RealType __u;
2123 	    do
2124 	      __u = __aurng();
2125 	    while (__u == 0.5);
2126 
2127 	    *__f++ = __p.a() + __p.b() * std::tan(__pi * __u);
2128 	  }
2129       }
2130 
2131   template<typename _RealType, typename _CharT, typename _Traits>
2132     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const cauchy_distribution<_RealType> & __x)2133     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2134 	       const cauchy_distribution<_RealType>& __x)
2135     {
2136       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2137       typedef typename __ostream_type::ios_base    __ios_base;
2138 
2139       const typename __ios_base::fmtflags __flags = __os.flags();
2140       const _CharT __fill = __os.fill();
2141       const std::streamsize __precision = __os.precision();
2142       const _CharT __space = __os.widen(' ');
2143       __os.flags(__ios_base::scientific | __ios_base::left);
2144       __os.fill(__space);
2145       __os.precision(std::numeric_limits<_RealType>::max_digits10);
2146 
2147       __os << __x.a() << __space << __x.b();
2148 
2149       __os.flags(__flags);
2150       __os.fill(__fill);
2151       __os.precision(__precision);
2152       return __os;
2153     }
2154 
2155   template<typename _RealType, typename _CharT, typename _Traits>
2156     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,cauchy_distribution<_RealType> & __x)2157     operator>>(std::basic_istream<_CharT, _Traits>& __is,
2158 	       cauchy_distribution<_RealType>& __x)
2159     {
2160       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2161       typedef typename __istream_type::ios_base    __ios_base;
2162 
2163       const typename __ios_base::fmtflags __flags = __is.flags();
2164       __is.flags(__ios_base::dec | __ios_base::skipws);
2165 
2166       _RealType __a, __b;
2167       if (__is >> __a >> __b)
2168 	__x.param(typename cauchy_distribution<_RealType>::
2169 		  param_type(__a, __b));
2170 
2171       __is.flags(__flags);
2172       return __is;
2173     }
2174 
2175 
2176   template<typename _RealType>
2177     template<typename _ForwardIterator,
2178 	     typename _UniformRandomNumberGenerator>
2179       void
2180       std::fisher_f_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng)2181       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2182 		      _UniformRandomNumberGenerator& __urng)
2183       {
2184 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2185 	while (__f != __t)
2186 	  *__f++ = ((_M_gd_x(__urng) * n()) / (_M_gd_y(__urng) * m()));
2187       }
2188 
2189   template<typename _RealType>
2190     template<typename _ForwardIterator,
2191 	     typename _UniformRandomNumberGenerator>
2192       void
2193       std::fisher_f_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)2194       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2195 		      _UniformRandomNumberGenerator& __urng,
2196 		      const param_type& __p)
2197       {
2198 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2199 	typedef typename std::gamma_distribution<result_type>::param_type
2200 	  param_type;
2201 	param_type __p1(__p.m() / 2);
2202 	param_type __p2(__p.n() / 2);
2203 	while (__f != __t)
2204 	  *__f++ = ((_M_gd_x(__urng, __p1) * n())
2205 		    / (_M_gd_y(__urng, __p2) * m()));
2206       }
2207 
2208   template<typename _RealType, typename _CharT, typename _Traits>
2209     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const fisher_f_distribution<_RealType> & __x)2210     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2211 	       const fisher_f_distribution<_RealType>& __x)
2212     {
2213       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2214       typedef typename __ostream_type::ios_base    __ios_base;
2215 
2216       const typename __ios_base::fmtflags __flags = __os.flags();
2217       const _CharT __fill = __os.fill();
2218       const std::streamsize __precision = __os.precision();
2219       const _CharT __space = __os.widen(' ');
2220       __os.flags(__ios_base::scientific | __ios_base::left);
2221       __os.fill(__space);
2222       __os.precision(std::numeric_limits<_RealType>::max_digits10);
2223 
2224       __os << __x.m() << __space << __x.n()
2225 	   << __space << __x._M_gd_x << __space << __x._M_gd_y;
2226 
2227       __os.flags(__flags);
2228       __os.fill(__fill);
2229       __os.precision(__precision);
2230       return __os;
2231     }
2232 
2233   template<typename _RealType, typename _CharT, typename _Traits>
2234     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,fisher_f_distribution<_RealType> & __x)2235     operator>>(std::basic_istream<_CharT, _Traits>& __is,
2236 	       fisher_f_distribution<_RealType>& __x)
2237     {
2238       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2239       typedef typename __istream_type::ios_base    __ios_base;
2240 
2241       const typename __ios_base::fmtflags __flags = __is.flags();
2242       __is.flags(__ios_base::dec | __ios_base::skipws);
2243 
2244       _RealType __m, __n;
2245       if (__is >> __m >> __n >> __x._M_gd_x >> __x._M_gd_y)
2246 	__x.param(typename fisher_f_distribution<_RealType>::
2247 		  param_type(__m, __n));
2248 
2249       __is.flags(__flags);
2250       return __is;
2251     }
2252 
2253 
2254   template<typename _RealType>
2255     template<typename _ForwardIterator,
2256 	     typename _UniformRandomNumberGenerator>
2257       void
2258       std::student_t_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng)2259       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2260 		      _UniformRandomNumberGenerator& __urng)
2261       {
2262 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2263 	while (__f != __t)
2264 	  *__f++ = _M_nd(__urng) * std::sqrt(n() / _M_gd(__urng));
2265       }
2266 
2267   template<typename _RealType>
2268     template<typename _ForwardIterator,
2269 	     typename _UniformRandomNumberGenerator>
2270       void
2271       std::student_t_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)2272       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2273 		      _UniformRandomNumberGenerator& __urng,
2274 		      const param_type& __p)
2275       {
2276 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2277 	typename std::gamma_distribution<result_type>::param_type
2278 	  __p2(__p.n() / 2, 2);
2279 	while (__f != __t)
2280 	  *__f++ =  _M_nd(__urng) * std::sqrt(__p.n() / _M_gd(__urng, __p2));
2281       }
2282 
2283   template<typename _RealType, typename _CharT, typename _Traits>
2284     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const student_t_distribution<_RealType> & __x)2285     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2286 	       const student_t_distribution<_RealType>& __x)
2287     {
2288       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2289       typedef typename __ostream_type::ios_base    __ios_base;
2290 
2291       const typename __ios_base::fmtflags __flags = __os.flags();
2292       const _CharT __fill = __os.fill();
2293       const std::streamsize __precision = __os.precision();
2294       const _CharT __space = __os.widen(' ');
2295       __os.flags(__ios_base::scientific | __ios_base::left);
2296       __os.fill(__space);
2297       __os.precision(std::numeric_limits<_RealType>::max_digits10);
2298 
2299       __os << __x.n() << __space << __x._M_nd << __space << __x._M_gd;
2300 
2301       __os.flags(__flags);
2302       __os.fill(__fill);
2303       __os.precision(__precision);
2304       return __os;
2305     }
2306 
2307   template<typename _RealType, typename _CharT, typename _Traits>
2308     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,student_t_distribution<_RealType> & __x)2309     operator>>(std::basic_istream<_CharT, _Traits>& __is,
2310 	       student_t_distribution<_RealType>& __x)
2311     {
2312       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2313       typedef typename __istream_type::ios_base    __ios_base;
2314 
2315       const typename __ios_base::fmtflags __flags = __is.flags();
2316       __is.flags(__ios_base::dec | __ios_base::skipws);
2317 
2318       _RealType __n;
2319       if (__is >> __n >> __x._M_nd >> __x._M_gd)
2320 	__x.param(typename student_t_distribution<_RealType>::param_type(__n));
2321 
2322       __is.flags(__flags);
2323       return __is;
2324     }
2325 
2326 
2327   template<typename _RealType>
2328     void
2329     gamma_distribution<_RealType>::param_type::
_M_initialize()2330     _M_initialize()
2331     {
2332       _M_malpha = _M_alpha < 1.0 ? _M_alpha + _RealType(1.0) : _M_alpha;
2333 
2334       const _RealType __a1 = _M_malpha - _RealType(1.0) / _RealType(3.0);
2335       _M_a2 = _RealType(1.0) / std::sqrt(_RealType(9.0) * __a1);
2336     }
2337 
2338   /**
2339    * Marsaglia, G. and Tsang, W. W.
2340    * "A Simple Method for Generating Gamma Variables"
2341    * ACM Transactions on Mathematical Software, 26, 3, 363-372, 2000.
2342    */
2343   template<typename _RealType>
2344     template<typename _UniformRandomNumberGenerator>
2345       typename gamma_distribution<_RealType>::result_type
2346       gamma_distribution<_RealType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __param)2347       operator()(_UniformRandomNumberGenerator& __urng,
2348 		 const param_type& __param)
2349       {
2350 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
2351 	  __aurng(__urng);
2352 
2353 	result_type __u, __v, __n;
2354 	const result_type __a1 = (__param._M_malpha
2355 				  - _RealType(1.0) / _RealType(3.0));
2356 
2357 	do
2358 	  {
2359 	    do
2360 	      {
2361 		__n = _M_nd(__urng);
2362 		__v = result_type(1.0) + __param._M_a2 * __n;
2363 	      }
2364 	    while (__v <= 0.0);
2365 
2366 	    __v = __v * __v * __v;
2367 	    __u = __aurng();
2368 	  }
2369 	while (__u > result_type(1.0) - 0.0331 * __n * __n * __n * __n
2370 	       && (std::log(__u) > (0.5 * __n * __n + __a1
2371 				    * (1.0 - __v + std::log(__v)))));
2372 
2373 	if (__param.alpha() == __param._M_malpha)
2374 	  return __a1 * __v * __param.beta();
2375 	else
2376 	  {
2377 	    do
2378 	      __u = __aurng();
2379 	    while (__u == 0.0);
2380 
2381 	    return (std::pow(__u, result_type(1.0) / __param.alpha())
2382 		    * __a1 * __v * __param.beta());
2383 	  }
2384       }
2385 
2386   template<typename _RealType>
2387     template<typename _ForwardIterator,
2388 	     typename _UniformRandomNumberGenerator>
2389       void
2390       gamma_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __param)2391       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2392 		      _UniformRandomNumberGenerator& __urng,
2393 		      const param_type& __param)
2394       {
2395 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2396 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
2397 	  __aurng(__urng);
2398 
2399 	result_type __u, __v, __n;
2400 	const result_type __a1 = (__param._M_malpha
2401 				  - _RealType(1.0) / _RealType(3.0));
2402 
2403 	if (__param.alpha() == __param._M_malpha)
2404 	  while (__f != __t)
2405 	    {
2406 	      do
2407 		{
2408 		  do
2409 		    {
2410 		      __n = _M_nd(__urng);
2411 		      __v = result_type(1.0) + __param._M_a2 * __n;
2412 		    }
2413 		  while (__v <= 0.0);
2414 
2415 		  __v = __v * __v * __v;
2416 		  __u = __aurng();
2417 		}
2418 	      while (__u > result_type(1.0) - 0.0331 * __n * __n * __n * __n
2419 		     && (std::log(__u) > (0.5 * __n * __n + __a1
2420 					  * (1.0 - __v + std::log(__v)))));
2421 
2422 	      *__f++ = __a1 * __v * __param.beta();
2423 	    }
2424 	else
2425 	  while (__f != __t)
2426 	    {
2427 	      do
2428 		{
2429 		  do
2430 		    {
2431 		      __n = _M_nd(__urng);
2432 		      __v = result_type(1.0) + __param._M_a2 * __n;
2433 		    }
2434 		  while (__v <= 0.0);
2435 
2436 		  __v = __v * __v * __v;
2437 		  __u = __aurng();
2438 		}
2439 	      while (__u > result_type(1.0) - 0.0331 * __n * __n * __n * __n
2440 		     && (std::log(__u) > (0.5 * __n * __n + __a1
2441 					  * (1.0 - __v + std::log(__v)))));
2442 
2443 	      do
2444 		__u = __aurng();
2445 	      while (__u == 0.0);
2446 
2447 	      *__f++ = (std::pow(__u, result_type(1.0) / __param.alpha())
2448 			* __a1 * __v * __param.beta());
2449 	    }
2450       }
2451 
2452   template<typename _RealType, typename _CharT, typename _Traits>
2453     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const gamma_distribution<_RealType> & __x)2454     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2455 	       const gamma_distribution<_RealType>& __x)
2456     {
2457       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2458       typedef typename __ostream_type::ios_base    __ios_base;
2459 
2460       const typename __ios_base::fmtflags __flags = __os.flags();
2461       const _CharT __fill = __os.fill();
2462       const std::streamsize __precision = __os.precision();
2463       const _CharT __space = __os.widen(' ');
2464       __os.flags(__ios_base::scientific | __ios_base::left);
2465       __os.fill(__space);
2466       __os.precision(std::numeric_limits<_RealType>::max_digits10);
2467 
2468       __os << __x.alpha() << __space << __x.beta()
2469 	   << __space << __x._M_nd;
2470 
2471       __os.flags(__flags);
2472       __os.fill(__fill);
2473       __os.precision(__precision);
2474       return __os;
2475     }
2476 
2477   template<typename _RealType, typename _CharT, typename _Traits>
2478     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,gamma_distribution<_RealType> & __x)2479     operator>>(std::basic_istream<_CharT, _Traits>& __is,
2480 	       gamma_distribution<_RealType>& __x)
2481     {
2482       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2483       typedef typename __istream_type::ios_base    __ios_base;
2484 
2485       const typename __ios_base::fmtflags __flags = __is.flags();
2486       __is.flags(__ios_base::dec | __ios_base::skipws);
2487 
2488       _RealType __alpha_val, __beta_val;
2489       if (__is >> __alpha_val >> __beta_val >> __x._M_nd)
2490 	__x.param(typename gamma_distribution<_RealType>::
2491 		  param_type(__alpha_val, __beta_val));
2492 
2493       __is.flags(__flags);
2494       return __is;
2495     }
2496 
2497 
2498   template<typename _RealType>
2499     template<typename _UniformRandomNumberGenerator>
2500       typename weibull_distribution<_RealType>::result_type
2501       weibull_distribution<_RealType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __p)2502       operator()(_UniformRandomNumberGenerator& __urng,
2503 		 const param_type& __p)
2504       {
2505 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
2506 	  __aurng(__urng);
2507 	return __p.b() * std::pow(-std::log(result_type(1) - __aurng()),
2508 				  result_type(1) / __p.a());
2509       }
2510 
2511   template<typename _RealType>
2512     template<typename _ForwardIterator,
2513 	     typename _UniformRandomNumberGenerator>
2514       void
2515       weibull_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)2516       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2517 		      _UniformRandomNumberGenerator& __urng,
2518 		      const param_type& __p)
2519       {
2520 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2521 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
2522 	  __aurng(__urng);
2523 	auto __inv_a = result_type(1) / __p.a();
2524 
2525 	while (__f != __t)
2526 	  *__f++ = __p.b() * std::pow(-std::log(result_type(1) - __aurng()),
2527 				      __inv_a);
2528       }
2529 
2530   template<typename _RealType, typename _CharT, typename _Traits>
2531     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const weibull_distribution<_RealType> & __x)2532     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2533 	       const weibull_distribution<_RealType>& __x)
2534     {
2535       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2536       typedef typename __ostream_type::ios_base    __ios_base;
2537 
2538       const typename __ios_base::fmtflags __flags = __os.flags();
2539       const _CharT __fill = __os.fill();
2540       const std::streamsize __precision = __os.precision();
2541       const _CharT __space = __os.widen(' ');
2542       __os.flags(__ios_base::scientific | __ios_base::left);
2543       __os.fill(__space);
2544       __os.precision(std::numeric_limits<_RealType>::max_digits10);
2545 
2546       __os << __x.a() << __space << __x.b();
2547 
2548       __os.flags(__flags);
2549       __os.fill(__fill);
2550       __os.precision(__precision);
2551       return __os;
2552     }
2553 
2554   template<typename _RealType, typename _CharT, typename _Traits>
2555     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,weibull_distribution<_RealType> & __x)2556     operator>>(std::basic_istream<_CharT, _Traits>& __is,
2557 	       weibull_distribution<_RealType>& __x)
2558     {
2559       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2560       typedef typename __istream_type::ios_base    __ios_base;
2561 
2562       const typename __ios_base::fmtflags __flags = __is.flags();
2563       __is.flags(__ios_base::dec | __ios_base::skipws);
2564 
2565       _RealType __a, __b;
2566       if (__is >> __a >> __b)
2567 	__x.param(typename weibull_distribution<_RealType>::
2568 		  param_type(__a, __b));
2569 
2570       __is.flags(__flags);
2571       return __is;
2572     }
2573 
2574 
2575   template<typename _RealType>
2576     template<typename _UniformRandomNumberGenerator>
2577       typename extreme_value_distribution<_RealType>::result_type
2578       extreme_value_distribution<_RealType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __p)2579       operator()(_UniformRandomNumberGenerator& __urng,
2580 		 const param_type& __p)
2581       {
2582 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
2583 	  __aurng(__urng);
2584 	return __p.a() - __p.b() * std::log(-std::log(result_type(1)
2585 						      - __aurng()));
2586       }
2587 
2588   template<typename _RealType>
2589     template<typename _ForwardIterator,
2590 	     typename _UniformRandomNumberGenerator>
2591       void
2592       extreme_value_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __p)2593       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2594 		      _UniformRandomNumberGenerator& __urng,
2595 		      const param_type& __p)
2596       {
2597 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2598 	__detail::_Adaptor<_UniformRandomNumberGenerator, result_type>
2599 	  __aurng(__urng);
2600 
2601 	while (__f != __t)
2602 	  *__f++ = __p.a() - __p.b() * std::log(-std::log(result_type(1)
2603 							  - __aurng()));
2604       }
2605 
2606   template<typename _RealType, typename _CharT, typename _Traits>
2607     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const extreme_value_distribution<_RealType> & __x)2608     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2609 	       const extreme_value_distribution<_RealType>& __x)
2610     {
2611       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2612       typedef typename __ostream_type::ios_base    __ios_base;
2613 
2614       const typename __ios_base::fmtflags __flags = __os.flags();
2615       const _CharT __fill = __os.fill();
2616       const std::streamsize __precision = __os.precision();
2617       const _CharT __space = __os.widen(' ');
2618       __os.flags(__ios_base::scientific | __ios_base::left);
2619       __os.fill(__space);
2620       __os.precision(std::numeric_limits<_RealType>::max_digits10);
2621 
2622       __os << __x.a() << __space << __x.b();
2623 
2624       __os.flags(__flags);
2625       __os.fill(__fill);
2626       __os.precision(__precision);
2627       return __os;
2628     }
2629 
2630   template<typename _RealType, typename _CharT, typename _Traits>
2631     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,extreme_value_distribution<_RealType> & __x)2632     operator>>(std::basic_istream<_CharT, _Traits>& __is,
2633 	       extreme_value_distribution<_RealType>& __x)
2634     {
2635       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2636       typedef typename __istream_type::ios_base    __ios_base;
2637 
2638       const typename __ios_base::fmtflags __flags = __is.flags();
2639       __is.flags(__ios_base::dec | __ios_base::skipws);
2640 
2641       _RealType __a, __b;
2642       if (__is >> __a >> __b)
2643 	__x.param(typename extreme_value_distribution<_RealType>::
2644 		  param_type(__a, __b));
2645 
2646       __is.flags(__flags);
2647       return __is;
2648     }
2649 
2650 
2651   template<typename _IntType>
2652     void
2653     discrete_distribution<_IntType>::param_type::
_M_initialize()2654     _M_initialize()
2655     {
2656       if (_M_prob.size() < 2)
2657 	{
2658 	  _M_prob.clear();
2659 	  return;
2660 	}
2661 
2662       const double __sum = std::accumulate(_M_prob.begin(),
2663 					   _M_prob.end(), 0.0);
2664       __glibcxx_assert(__sum > 0);
2665       // Now normalize the probabilites.
2666       __detail::__normalize(_M_prob.begin(), _M_prob.end(), _M_prob.begin(),
2667 			    __sum);
2668       // Accumulate partial sums.
2669       _M_cp.reserve(_M_prob.size());
2670       std::partial_sum(_M_prob.begin(), _M_prob.end(),
2671 		       std::back_inserter(_M_cp));
2672       // Make sure the last cumulative probability is one.
2673       _M_cp[_M_cp.size() - 1] = 1.0;
2674     }
2675 
2676   template<typename _IntType>
2677     template<typename _Func>
2678       discrete_distribution<_IntType>::param_type::
param_type(size_t __nw,double __xmin,double __xmax,_Func __fw)2679       param_type(size_t __nw, double __xmin, double __xmax, _Func __fw)
2680       : _M_prob(), _M_cp()
2681       {
2682 	const size_t __n = __nw == 0 ? 1 : __nw;
2683 	const double __delta = (__xmax - __xmin) / __n;
2684 
2685 	_M_prob.reserve(__n);
2686 	for (size_t __k = 0; __k < __nw; ++__k)
2687 	  _M_prob.push_back(__fw(__xmin + __k * __delta + 0.5 * __delta));
2688 
2689 	_M_initialize();
2690       }
2691 
2692   template<typename _IntType>
2693     template<typename _UniformRandomNumberGenerator>
2694       typename discrete_distribution<_IntType>::result_type
2695       discrete_distribution<_IntType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __param)2696       operator()(_UniformRandomNumberGenerator& __urng,
2697 		 const param_type& __param)
2698       {
2699 	if (__param._M_cp.empty())
2700 	  return result_type(0);
2701 
2702 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
2703 	  __aurng(__urng);
2704 
2705 	const double __p = __aurng();
2706 	auto __pos = std::lower_bound(__param._M_cp.begin(),
2707 				      __param._M_cp.end(), __p);
2708 
2709 	return __pos - __param._M_cp.begin();
2710       }
2711 
2712   template<typename _IntType>
2713     template<typename _ForwardIterator,
2714 	     typename _UniformRandomNumberGenerator>
2715       void
2716       discrete_distribution<_IntType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __param)2717       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2718 		      _UniformRandomNumberGenerator& __urng,
2719 		      const param_type& __param)
2720       {
2721 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2722 
2723 	if (__param._M_cp.empty())
2724 	  {
2725 	    while (__f != __t)
2726 	      *__f++ = result_type(0);
2727 	    return;
2728 	  }
2729 
2730 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
2731 	  __aurng(__urng);
2732 
2733 	while (__f != __t)
2734 	  {
2735 	    const double __p = __aurng();
2736 	    auto __pos = std::lower_bound(__param._M_cp.begin(),
2737 					  __param._M_cp.end(), __p);
2738 
2739 	    *__f++ = __pos - __param._M_cp.begin();
2740 	  }
2741       }
2742 
2743   template<typename _IntType, typename _CharT, typename _Traits>
2744     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const discrete_distribution<_IntType> & __x)2745     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2746 	       const discrete_distribution<_IntType>& __x)
2747     {
2748       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2749       typedef typename __ostream_type::ios_base    __ios_base;
2750 
2751       const typename __ios_base::fmtflags __flags = __os.flags();
2752       const _CharT __fill = __os.fill();
2753       const std::streamsize __precision = __os.precision();
2754       const _CharT __space = __os.widen(' ');
2755       __os.flags(__ios_base::scientific | __ios_base::left);
2756       __os.fill(__space);
2757       __os.precision(std::numeric_limits<double>::max_digits10);
2758 
2759       std::vector<double> __prob = __x.probabilities();
2760       __os << __prob.size();
2761       for (auto __dit = __prob.begin(); __dit != __prob.end(); ++__dit)
2762 	__os << __space << *__dit;
2763 
2764       __os.flags(__flags);
2765       __os.fill(__fill);
2766       __os.precision(__precision);
2767       return __os;
2768     }
2769 
2770 namespace __detail
2771 {
2772   template<typename _ValT, typename _CharT, typename _Traits>
2773     basic_istream<_CharT, _Traits>&
__extract_params(basic_istream<_CharT,_Traits> & __is,vector<_ValT> & __vals,size_t __n)2774     __extract_params(basic_istream<_CharT, _Traits>& __is,
2775 		     vector<_ValT>& __vals, size_t __n)
2776     {
2777       __vals.reserve(__n);
2778       while (__n--)
2779 	{
2780 	  _ValT __val;
2781 	  if (__is >> __val)
2782 	    __vals.push_back(__val);
2783 	  else
2784 	    break;
2785 	}
2786       return __is;
2787     }
2788 } // namespace __detail
2789 
2790   template<typename _IntType, typename _CharT, typename _Traits>
2791     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,discrete_distribution<_IntType> & __x)2792     operator>>(std::basic_istream<_CharT, _Traits>& __is,
2793 	       discrete_distribution<_IntType>& __x)
2794     {
2795       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
2796       typedef typename __istream_type::ios_base    __ios_base;
2797 
2798       const typename __ios_base::fmtflags __flags = __is.flags();
2799       __is.flags(__ios_base::dec | __ios_base::skipws);
2800 
2801       size_t __n;
2802       if (__is >> __n)
2803 	{
2804 	  std::vector<double> __prob_vec;
2805 	  if (__detail::__extract_params(__is, __prob_vec, __n))
2806 	    __x.param({__prob_vec.begin(), __prob_vec.end()});
2807 	}
2808 
2809       __is.flags(__flags);
2810       return __is;
2811     }
2812 
2813 
2814   template<typename _RealType>
2815     void
2816     piecewise_constant_distribution<_RealType>::param_type::
_M_initialize()2817     _M_initialize()
2818     {
2819       if (_M_int.size() < 2
2820 	  || (_M_int.size() == 2
2821 	      && _M_int[0] == _RealType(0)
2822 	      && _M_int[1] == _RealType(1)))
2823 	{
2824 	  _M_int.clear();
2825 	  _M_den.clear();
2826 	  return;
2827 	}
2828 
2829       const double __sum = std::accumulate(_M_den.begin(),
2830 					   _M_den.end(), 0.0);
2831       __glibcxx_assert(__sum > 0);
2832 
2833       __detail::__normalize(_M_den.begin(), _M_den.end(), _M_den.begin(),
2834 			    __sum);
2835 
2836       _M_cp.reserve(_M_den.size());
2837       std::partial_sum(_M_den.begin(), _M_den.end(),
2838 		       std::back_inserter(_M_cp));
2839 
2840       // Make sure the last cumulative probability is one.
2841       _M_cp[_M_cp.size() - 1] = 1.0;
2842 
2843       for (size_t __k = 0; __k < _M_den.size(); ++__k)
2844 	_M_den[__k] /= _M_int[__k + 1] - _M_int[__k];
2845     }
2846 
2847   template<typename _RealType>
2848     template<typename _InputIteratorB, typename _InputIteratorW>
2849       piecewise_constant_distribution<_RealType>::param_type::
param_type(_InputIteratorB __bbegin,_InputIteratorB __bend,_InputIteratorW __wbegin)2850       param_type(_InputIteratorB __bbegin,
2851 		 _InputIteratorB __bend,
2852 		 _InputIteratorW __wbegin)
2853       : _M_int(), _M_den(), _M_cp()
2854       {
2855 	if (__bbegin != __bend)
2856 	  {
2857 	    for (;;)
2858 	      {
2859 		_M_int.push_back(*__bbegin);
2860 		++__bbegin;
2861 		if (__bbegin == __bend)
2862 		  break;
2863 
2864 		_M_den.push_back(*__wbegin);
2865 		++__wbegin;
2866 	      }
2867 	  }
2868 
2869 	_M_initialize();
2870       }
2871 
2872   template<typename _RealType>
2873     template<typename _Func>
2874       piecewise_constant_distribution<_RealType>::param_type::
param_type(initializer_list<_RealType> __bl,_Func __fw)2875       param_type(initializer_list<_RealType> __bl, _Func __fw)
2876       : _M_int(), _M_den(), _M_cp()
2877       {
2878 	_M_int.reserve(__bl.size());
2879 	for (auto __biter = __bl.begin(); __biter != __bl.end(); ++__biter)
2880 	  _M_int.push_back(*__biter);
2881 
2882 	_M_den.reserve(_M_int.size() - 1);
2883 	for (size_t __k = 0; __k < _M_int.size() - 1; ++__k)
2884 	  _M_den.push_back(__fw(0.5 * (_M_int[__k + 1] + _M_int[__k])));
2885 
2886 	_M_initialize();
2887       }
2888 
2889   template<typename _RealType>
2890     template<typename _Func>
2891       piecewise_constant_distribution<_RealType>::param_type::
param_type(size_t __nw,_RealType __xmin,_RealType __xmax,_Func __fw)2892       param_type(size_t __nw, _RealType __xmin, _RealType __xmax, _Func __fw)
2893       : _M_int(), _M_den(), _M_cp()
2894       {
2895 	const size_t __n = __nw == 0 ? 1 : __nw;
2896 	const _RealType __delta = (__xmax - __xmin) / __n;
2897 
2898 	_M_int.reserve(__n + 1);
2899 	for (size_t __k = 0; __k <= __nw; ++__k)
2900 	  _M_int.push_back(__xmin + __k * __delta);
2901 
2902 	_M_den.reserve(__n);
2903 	for (size_t __k = 0; __k < __nw; ++__k)
2904 	  _M_den.push_back(__fw(_M_int[__k] + 0.5 * __delta));
2905 
2906 	_M_initialize();
2907       }
2908 
2909   template<typename _RealType>
2910     template<typename _UniformRandomNumberGenerator>
2911       typename piecewise_constant_distribution<_RealType>::result_type
2912       piecewise_constant_distribution<_RealType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __param)2913       operator()(_UniformRandomNumberGenerator& __urng,
2914 		 const param_type& __param)
2915       {
2916 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
2917 	  __aurng(__urng);
2918 
2919 	const double __p = __aurng();
2920 	if (__param._M_cp.empty())
2921 	  return __p;
2922 
2923 	auto __pos = std::lower_bound(__param._M_cp.begin(),
2924 				      __param._M_cp.end(), __p);
2925 	const size_t __i = __pos - __param._M_cp.begin();
2926 
2927 	const double __pref = __i > 0 ? __param._M_cp[__i - 1] : 0.0;
2928 
2929 	return __param._M_int[__i] + (__p - __pref) / __param._M_den[__i];
2930       }
2931 
2932   template<typename _RealType>
2933     template<typename _ForwardIterator,
2934 	     typename _UniformRandomNumberGenerator>
2935       void
2936       piecewise_constant_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __param)2937       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
2938 		      _UniformRandomNumberGenerator& __urng,
2939 		      const param_type& __param)
2940       {
2941 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2942 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
2943 	  __aurng(__urng);
2944 
2945 	if (__param._M_cp.empty())
2946 	  {
2947 	    while (__f != __t)
2948 	      *__f++ = __aurng();
2949 	    return;
2950 	  }
2951 
2952 	while (__f != __t)
2953 	  {
2954 	    const double __p = __aurng();
2955 
2956 	    auto __pos = std::lower_bound(__param._M_cp.begin(),
2957 					  __param._M_cp.end(), __p);
2958 	    const size_t __i = __pos - __param._M_cp.begin();
2959 
2960 	    const double __pref = __i > 0 ? __param._M_cp[__i - 1] : 0.0;
2961 
2962 	    *__f++ = (__param._M_int[__i]
2963 		      + (__p - __pref) / __param._M_den[__i]);
2964 	  }
2965       }
2966 
2967   template<typename _RealType, typename _CharT, typename _Traits>
2968     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const piecewise_constant_distribution<_RealType> & __x)2969     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
2970 	       const piecewise_constant_distribution<_RealType>& __x)
2971     {
2972       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
2973       typedef typename __ostream_type::ios_base    __ios_base;
2974 
2975       const typename __ios_base::fmtflags __flags = __os.flags();
2976       const _CharT __fill = __os.fill();
2977       const std::streamsize __precision = __os.precision();
2978       const _CharT __space = __os.widen(' ');
2979       __os.flags(__ios_base::scientific | __ios_base::left);
2980       __os.fill(__space);
2981       __os.precision(std::numeric_limits<_RealType>::max_digits10);
2982 
2983       std::vector<_RealType> __int = __x.intervals();
2984       __os << __int.size() - 1;
2985 
2986       for (auto __xit = __int.begin(); __xit != __int.end(); ++__xit)
2987 	__os << __space << *__xit;
2988 
2989       std::vector<double> __den = __x.densities();
2990       for (auto __dit = __den.begin(); __dit != __den.end(); ++__dit)
2991 	__os << __space << *__dit;
2992 
2993       __os.flags(__flags);
2994       __os.fill(__fill);
2995       __os.precision(__precision);
2996       return __os;
2997     }
2998 
2999   template<typename _RealType, typename _CharT, typename _Traits>
3000     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,piecewise_constant_distribution<_RealType> & __x)3001     operator>>(std::basic_istream<_CharT, _Traits>& __is,
3002 	       piecewise_constant_distribution<_RealType>& __x)
3003     {
3004       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
3005       typedef typename __istream_type::ios_base    __ios_base;
3006 
3007       const typename __ios_base::fmtflags __flags = __is.flags();
3008       __is.flags(__ios_base::dec | __ios_base::skipws);
3009 
3010       size_t __n;
3011       if (__is >> __n)
3012 	{
3013 	  std::vector<_RealType> __int_vec;
3014 	  if (__detail::__extract_params(__is, __int_vec, __n + 1))
3015 	    {
3016 	      std::vector<double> __den_vec;
3017 	      if (__detail::__extract_params(__is, __den_vec, __n))
3018 		{
3019 		  __x.param({ __int_vec.begin(), __int_vec.end(),
3020 			      __den_vec.begin() });
3021 		}
3022 	    }
3023 	}
3024 
3025       __is.flags(__flags);
3026       return __is;
3027     }
3028 
3029 
3030   template<typename _RealType>
3031     void
3032     piecewise_linear_distribution<_RealType>::param_type::
_M_initialize()3033     _M_initialize()
3034     {
3035       if (_M_int.size() < 2
3036 	  || (_M_int.size() == 2
3037 	      && _M_int[0] == _RealType(0)
3038 	      && _M_int[1] == _RealType(1)
3039 	      && _M_den[0] == _M_den[1]))
3040 	{
3041 	  _M_int.clear();
3042 	  _M_den.clear();
3043 	  return;
3044 	}
3045 
3046       double __sum = 0.0;
3047       _M_cp.reserve(_M_int.size() - 1);
3048       _M_m.reserve(_M_int.size() - 1);
3049       for (size_t __k = 0; __k < _M_int.size() - 1; ++__k)
3050 	{
3051 	  const _RealType __delta = _M_int[__k + 1] - _M_int[__k];
3052 	  __sum += 0.5 * (_M_den[__k + 1] + _M_den[__k]) * __delta;
3053 	  _M_cp.push_back(__sum);
3054 	  _M_m.push_back((_M_den[__k + 1] - _M_den[__k]) / __delta);
3055 	}
3056       __glibcxx_assert(__sum > 0);
3057 
3058       //  Now normalize the densities...
3059       __detail::__normalize(_M_den.begin(), _M_den.end(), _M_den.begin(),
3060 			    __sum);
3061       //  ... and partial sums...
3062       __detail::__normalize(_M_cp.begin(), _M_cp.end(), _M_cp.begin(), __sum);
3063       //  ... and slopes.
3064       __detail::__normalize(_M_m.begin(), _M_m.end(), _M_m.begin(), __sum);
3065 
3066       //  Make sure the last cumulative probablility is one.
3067       _M_cp[_M_cp.size() - 1] = 1.0;
3068      }
3069 
3070   template<typename _RealType>
3071     template<typename _InputIteratorB, typename _InputIteratorW>
3072       piecewise_linear_distribution<_RealType>::param_type::
param_type(_InputIteratorB __bbegin,_InputIteratorB __bend,_InputIteratorW __wbegin)3073       param_type(_InputIteratorB __bbegin,
3074 		 _InputIteratorB __bend,
3075 		 _InputIteratorW __wbegin)
3076       : _M_int(), _M_den(), _M_cp(), _M_m()
3077       {
3078 	for (; __bbegin != __bend; ++__bbegin, ++__wbegin)
3079 	  {
3080 	    _M_int.push_back(*__bbegin);
3081 	    _M_den.push_back(*__wbegin);
3082 	  }
3083 
3084 	_M_initialize();
3085       }
3086 
3087   template<typename _RealType>
3088     template<typename _Func>
3089       piecewise_linear_distribution<_RealType>::param_type::
param_type(initializer_list<_RealType> __bl,_Func __fw)3090       param_type(initializer_list<_RealType> __bl, _Func __fw)
3091       : _M_int(), _M_den(), _M_cp(), _M_m()
3092       {
3093 	_M_int.reserve(__bl.size());
3094 	_M_den.reserve(__bl.size());
3095 	for (auto __biter = __bl.begin(); __biter != __bl.end(); ++__biter)
3096 	  {
3097 	    _M_int.push_back(*__biter);
3098 	    _M_den.push_back(__fw(*__biter));
3099 	  }
3100 
3101 	_M_initialize();
3102       }
3103 
3104   template<typename _RealType>
3105     template<typename _Func>
3106       piecewise_linear_distribution<_RealType>::param_type::
param_type(size_t __nw,_RealType __xmin,_RealType __xmax,_Func __fw)3107       param_type(size_t __nw, _RealType __xmin, _RealType __xmax, _Func __fw)
3108       : _M_int(), _M_den(), _M_cp(), _M_m()
3109       {
3110 	const size_t __n = __nw == 0 ? 1 : __nw;
3111 	const _RealType __delta = (__xmax - __xmin) / __n;
3112 
3113 	_M_int.reserve(__n + 1);
3114 	_M_den.reserve(__n + 1);
3115 	for (size_t __k = 0; __k <= __nw; ++__k)
3116 	  {
3117 	    _M_int.push_back(__xmin + __k * __delta);
3118 	    _M_den.push_back(__fw(_M_int[__k] + __delta));
3119 	  }
3120 
3121 	_M_initialize();
3122       }
3123 
3124   template<typename _RealType>
3125     template<typename _UniformRandomNumberGenerator>
3126       typename piecewise_linear_distribution<_RealType>::result_type
3127       piecewise_linear_distribution<_RealType>::
operator ()(_UniformRandomNumberGenerator & __urng,const param_type & __param)3128       operator()(_UniformRandomNumberGenerator& __urng,
3129 		 const param_type& __param)
3130       {
3131 	__detail::_Adaptor<_UniformRandomNumberGenerator, double>
3132 	  __aurng(__urng);
3133 
3134 	const double __p = __aurng();
3135 	if (__param._M_cp.empty())
3136 	  return __p;
3137 
3138 	auto __pos = std::lower_bound(__param._M_cp.begin(),
3139 				      __param._M_cp.end(), __p);
3140 	const size_t __i = __pos - __param._M_cp.begin();
3141 
3142 	const double __pref = __i > 0 ? __param._M_cp[__i - 1] : 0.0;
3143 
3144 	const double __a = 0.5 * __param._M_m[__i];
3145 	const double __b = __param._M_den[__i];
3146 	const double __cm = __p - __pref;
3147 
3148 	_RealType __x = __param._M_int[__i];
3149 	if (__a == 0)
3150 	  __x += __cm / __b;
3151 	else
3152 	  {
3153 	    const double __d = __b * __b + 4.0 * __a * __cm;
3154 	    __x += 0.5 * (std::sqrt(__d) - __b) / __a;
3155           }
3156 
3157         return __x;
3158       }
3159 
3160   template<typename _RealType>
3161     template<typename _ForwardIterator,
3162 	     typename _UniformRandomNumberGenerator>
3163       void
3164       piecewise_linear_distribution<_RealType>::
__generate_impl(_ForwardIterator __f,_ForwardIterator __t,_UniformRandomNumberGenerator & __urng,const param_type & __param)3165       __generate_impl(_ForwardIterator __f, _ForwardIterator __t,
3166 		      _UniformRandomNumberGenerator& __urng,
3167 		      const param_type& __param)
3168       {
3169 	__glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3170 	// We could duplicate everything from operator()...
3171 	while (__f != __t)
3172 	  *__f++ = this->operator()(__urng, __param);
3173       }
3174 
3175   template<typename _RealType, typename _CharT, typename _Traits>
3176     std::basic_ostream<_CharT, _Traits>&
operator <<(std::basic_ostream<_CharT,_Traits> & __os,const piecewise_linear_distribution<_RealType> & __x)3177     operator<<(std::basic_ostream<_CharT, _Traits>& __os,
3178 	       const piecewise_linear_distribution<_RealType>& __x)
3179     {
3180       typedef std::basic_ostream<_CharT, _Traits>  __ostream_type;
3181       typedef typename __ostream_type::ios_base    __ios_base;
3182 
3183       const typename __ios_base::fmtflags __flags = __os.flags();
3184       const _CharT __fill = __os.fill();
3185       const std::streamsize __precision = __os.precision();
3186       const _CharT __space = __os.widen(' ');
3187       __os.flags(__ios_base::scientific | __ios_base::left);
3188       __os.fill(__space);
3189       __os.precision(std::numeric_limits<_RealType>::max_digits10);
3190 
3191       std::vector<_RealType> __int = __x.intervals();
3192       __os << __int.size() - 1;
3193 
3194       for (auto __xit = __int.begin(); __xit != __int.end(); ++__xit)
3195 	__os << __space << *__xit;
3196 
3197       std::vector<double> __den = __x.densities();
3198       for (auto __dit = __den.begin(); __dit != __den.end(); ++__dit)
3199 	__os << __space << *__dit;
3200 
3201       __os.flags(__flags);
3202       __os.fill(__fill);
3203       __os.precision(__precision);
3204       return __os;
3205     }
3206 
3207   template<typename _RealType, typename _CharT, typename _Traits>
3208     std::basic_istream<_CharT, _Traits>&
operator >>(std::basic_istream<_CharT,_Traits> & __is,piecewise_linear_distribution<_RealType> & __x)3209     operator>>(std::basic_istream<_CharT, _Traits>& __is,
3210 	       piecewise_linear_distribution<_RealType>& __x)
3211     {
3212       typedef std::basic_istream<_CharT, _Traits>  __istream_type;
3213       typedef typename __istream_type::ios_base    __ios_base;
3214 
3215       const typename __ios_base::fmtflags __flags = __is.flags();
3216       __is.flags(__ios_base::dec | __ios_base::skipws);
3217 
3218       size_t __n;
3219       if (__is >> __n)
3220 	{
3221 	  vector<_RealType> __int_vec;
3222 	  if (__detail::__extract_params(__is, __int_vec, __n + 1))
3223 	    {
3224 	      vector<double> __den_vec;
3225 	      if (__detail::__extract_params(__is, __den_vec, __n + 1))
3226 		{
3227 		  __x.param({ __int_vec.begin(), __int_vec.end(),
3228 			      __den_vec.begin() });
3229 		}
3230 	    }
3231 	}
3232       __is.flags(__flags);
3233       return __is;
3234     }
3235 
3236 
3237   template<typename _IntType>
seed_seq(std::initializer_list<_IntType> __il)3238     seed_seq::seed_seq(std::initializer_list<_IntType> __il)
3239     {
3240       for (auto __iter = __il.begin(); __iter != __il.end(); ++__iter)
3241 	_M_v.push_back(__detail::__mod<result_type,
3242 		       __detail::_Shift<result_type, 32>::__value>(*__iter));
3243     }
3244 
3245   template<typename _InputIterator>
seed_seq(_InputIterator __begin,_InputIterator __end)3246     seed_seq::seed_seq(_InputIterator __begin, _InputIterator __end)
3247     {
3248       for (_InputIterator __iter = __begin; __iter != __end; ++__iter)
3249 	_M_v.push_back(__detail::__mod<result_type,
3250 		       __detail::_Shift<result_type, 32>::__value>(*__iter));
3251     }
3252 
3253   template<typename _RandomAccessIterator>
3254     void
generate(_RandomAccessIterator __begin,_RandomAccessIterator __end)3255     seed_seq::generate(_RandomAccessIterator __begin,
3256 		       _RandomAccessIterator __end)
3257     {
3258       typedef typename iterator_traits<_RandomAccessIterator>::value_type
3259         _Type;
3260 
3261       if (__begin == __end)
3262 	return;
3263 
3264       std::fill(__begin, __end, _Type(0x8b8b8b8bu));
3265 
3266       const size_t __n = __end - __begin;
3267       const size_t __s = _M_v.size();
3268       const size_t __t = (__n >= 623) ? 11
3269 		       : (__n >=  68) ? 7
3270 		       : (__n >=  39) ? 5
3271 		       : (__n >=   7) ? 3
3272 		       : (__n - 1) / 2;
3273       const size_t __p = (__n - __t) / 2;
3274       const size_t __q = __p + __t;
3275       const size_t __m = std::max(size_t(__s + 1), __n);
3276 
3277       for (size_t __k = 0; __k < __m; ++__k)
3278 	{
3279 	  _Type __arg = (__begin[__k % __n]
3280 			 ^ __begin[(__k + __p) % __n]
3281 			 ^ __begin[(__k - 1) % __n]);
3282 	  _Type __r1 = __arg ^ (__arg >> 27);
3283 	  __r1 = __detail::__mod<_Type,
3284 		    __detail::_Shift<_Type, 32>::__value>(1664525u * __r1);
3285 	  _Type __r2 = __r1;
3286 	  if (__k == 0)
3287 	    __r2 += __s;
3288 	  else if (__k <= __s)
3289 	    __r2 += __k % __n + _M_v[__k - 1];
3290 	  else
3291 	    __r2 += __k % __n;
3292 	  __r2 = __detail::__mod<_Type,
3293 	           __detail::_Shift<_Type, 32>::__value>(__r2);
3294 	  __begin[(__k + __p) % __n] += __r1;
3295 	  __begin[(__k + __q) % __n] += __r2;
3296 	  __begin[__k % __n] = __r2;
3297 	}
3298 
3299       for (size_t __k = __m; __k < __m + __n; ++__k)
3300 	{
3301 	  _Type __arg = (__begin[__k % __n]
3302 			 + __begin[(__k + __p) % __n]
3303 			 + __begin[(__k - 1) % __n]);
3304 	  _Type __r3 = __arg ^ (__arg >> 27);
3305 	  __r3 = __detail::__mod<_Type,
3306 		   __detail::_Shift<_Type, 32>::__value>(1566083941u * __r3);
3307 	  _Type __r4 = __r3 - __k % __n;
3308 	  __r4 = __detail::__mod<_Type,
3309 	           __detail::_Shift<_Type, 32>::__value>(__r4);
3310 	  __begin[(__k + __p) % __n] ^= __r3;
3311 	  __begin[(__k + __q) % __n] ^= __r4;
3312 	  __begin[__k % __n] = __r4;
3313 	}
3314     }
3315 
3316   template<typename _RealType, size_t __bits,
3317 	   typename _UniformRandomNumberGenerator>
3318     _RealType
3319     generate_canonical(_UniformRandomNumberGenerator& __urng)
3320     {
3321       static_assert(std::is_floating_point<_RealType>::value,
3322 		    "template argument must be a floating point type");
3323 
3324       const size_t __b
3325 	= std::min(static_cast<size_t>(std::numeric_limits<_RealType>::digits),
3326                    __bits);
3327       const long double __r = static_cast<long double>(__urng.max())
3328 			    - static_cast<long double>(__urng.min()) + 1.0L;
3329       const size_t __log2r = std::log(__r) / std::log(2.0L);
3330       const size_t __m = std::max<size_t>(1UL,
3331 					  (__b + __log2r - 1UL) / __log2r);
3332       _RealType __ret;
3333       _RealType __sum = _RealType(0);
3334       _RealType __tmp = _RealType(1);
3335       for (size_t __k = __m; __k != 0; --__k)
3336 	{
3337 	  __sum += _RealType(__urng() - __urng.min()) * __tmp;
3338 	  __tmp *= __r;
3339 	}
3340       __ret = __sum / __tmp;
3341       if (__builtin_expect(__ret >= _RealType(1), 0))
3342 	{
3343 #if _GLIBCXX_USE_C99_MATH_TR1
3344 	  __ret = std::nextafter(_RealType(1), _RealType(0));
3345 #else
3346 	  __ret = _RealType(1)
3347 	    - std::numeric_limits<_RealType>::epsilon() / _RealType(2);
3348 #endif
3349 	}
3350       return __ret;
3351     }
3352 
3353 _GLIBCXX_END_NAMESPACE_VERSION
3354 } // namespace
3355 
3356 #endif
3357