1 //===----------------------------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 // <algorithm>
11
12 // template<RandomAccessIterator Iter, StrictWeakOrder<auto, Iter::value_type> Compare>
13 // requires ShuffleIterator<Iter>
14 // && CopyConstructible<Compare>
15 // void
16 // partial_sort(Iter first, Iter middle, Iter last, Compare comp);
17
18 #include <algorithm>
19 #include <vector>
20 #include <functional>
21 #include <cassert>
22 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
23 #include <memory>
24
25 struct indirect_less
26 {
27 template <class P>
operator ()indirect_less28 bool operator()(const P& x, const P& y)
29 {return *x < *y;}
30 };
31
32 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES
33
34 void
test_larger_sorts(unsigned N,unsigned M)35 test_larger_sorts(unsigned N, unsigned M)
36 {
37 assert(N != 0);
38 int* array = new int[N];
39 for (int i = 0; i < N; ++i)
40 array[i] = i;
41 std::random_shuffle(array, array+N);
42 std::partial_sort(array, array+M, array+N, std::greater<int>());
43 for (int i = 0; i < M; ++i)
44 assert(array[i] == N-i-1);
45 delete [] array;
46 }
47
48 void
test_larger_sorts(unsigned N)49 test_larger_sorts(unsigned N)
50 {
51 test_larger_sorts(N, 0);
52 test_larger_sorts(N, 1);
53 test_larger_sorts(N, 2);
54 test_larger_sorts(N, 3);
55 test_larger_sorts(N, N/2-1);
56 test_larger_sorts(N, N/2);
57 test_larger_sorts(N, N/2+1);
58 test_larger_sorts(N, N-2);
59 test_larger_sorts(N, N-1);
60 test_larger_sorts(N, N);
61 }
62
main()63 int main()
64 {
65 int i = 0;
66 std::partial_sort(&i, &i, &i);
67 assert(i == 0);
68 test_larger_sorts(10);
69 test_larger_sorts(256);
70 test_larger_sorts(257);
71 test_larger_sorts(499);
72 test_larger_sorts(500);
73 test_larger_sorts(997);
74 test_larger_sorts(1000);
75 test_larger_sorts(1009);
76
77 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
78 {
79 std::vector<std::unique_ptr<int> > v(1000);
80 for (int i = 0; i < v.size(); ++i)
81 v[i].reset(new int(i));
82 std::partial_sort(v.begin(), v.begin() + v.size()/2, v.end(), indirect_less());
83 for (int i = 0; i < v.size()/2; ++i)
84 assert(*v[i] == i);
85 }
86 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES
87 }
88