xref: /dragonfly/games/cribbage/score.c (revision 6b5c5d0d)
1 /*-
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * @(#)score.c	8.1 (Berkeley) 5/31/93
34  * $FreeBSD: src/games/cribbage/score.c,v 1.6 1999/11/30 03:48:47 billf Exp $
35  * $DragonFly: src/games/cribbage/score.c,v 1.3 2005/08/03 13:31:00 eirikn Exp $
36  */
37 
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 
42 #include "cribbage.h"
43 
44 static int	fifteens(CARD[], int);
45 static int	pairuns(CARD[], int);
46 /*
47  * the following arrays give the sum of the scores of the (50 2)*48 = 58800
48  * hands obtainable for the crib given the two cards whose ranks index the
49  * array.  the two arrays are for the case where the suits are equal and
50  * not equal respectively
51  */
52 const long crbescr[169] = {
53     -10000, 271827, 278883, 332319, 347769, 261129, 250653, 253203, 248259,
54     243435, 256275, 237435, 231051, -10000, -10000, 412815, 295707, 349497,
55     267519, 262521, 259695, 254019, 250047, 262887, 244047, 237663, -10000,
56     -10000, -10000, 333987, 388629, 262017, 266787, 262971, 252729, 254475,
57     267315, 248475, 242091, -10000, -10000, -10000, -10000, 422097, 302787,
58     256437, 263751, 257883, 254271, 267111, 248271, 241887, -10000, -10000,
59     -10000, -10000, -10000, 427677, 387837, 349173, 347985, 423861, 436701,
60     417861, 411477, -10000, -10000, -10000, -10000, -10000, -10000, 336387,
61     298851, 338667, 236487, 249327, 230487, 224103, -10000, -10000, -10000,
62     -10000, -10000, -10000, -10000, 408483, 266691, 229803, 246195, 227355,
63     220971, -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000,
64     300675, 263787, 241695, 226407, 220023, -10000, -10000, -10000, -10000,
65     -10000, -10000, -10000, -10000, -10000, 295635, 273543, 219771, 216939,
66     -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000,
67     -10000, 306519, 252747, 211431, -10000, -10000, -10000, -10000, -10000,
68     -10000, -10000, -10000, -10000, -10000, -10000, 304287, 262971, -10000,
69     -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000,
70     -10000, -10000, 244131, -10000, -10000, -10000, -10000, -10000, -10000,
71     -10000, -10000, -10000, -10000, -10000, -10000, -10000
72 };
73 
74 const long crbnescr[169] = {
75     325272, 260772, 267828, 321264, 336714, 250074, 239598, 242148, 237204,
76     232380, 246348, 226380, 219996, -10000, 342528, 401760, 284652, 338442,
77     256464, 251466, 248640, 242964, 238992, 252960, 232992, 226608, -10000,
78     -10000, 362280, 322932, 377574, 250962, 255732, 251916, 241674, 243420,
79     257388, 237420, 231036, -10000, -10000, -10000, 360768, 411042, 291732,
80     245382, 252696, 246828, 243216, 257184, 237216, 230832, -10000, -10000,
81     -10000, -10000, 528768, 416622, 376782, 338118, 336930, 412806, 426774,
82     406806, 400422, -10000, -10000, -10000, -10000, -10000, 369864, 325332,
83     287796, 327612, 225432, 239400, 219432, 213048, -10000, -10000, -10000,
84     -10000, -10000, -10000, 359160, 397428, 255636, 218748, 236268, 216300,
85     209916, -10000, -10000, -10000, -10000, -10000, -10000, -10000, 331320,
86     289620, 252732, 231768, 215352, 208968, -10000, -10000, -10000, -10000,
87     -10000, -10000, -10000, -10000, 325152, 284580, 263616, 208716, 205884,
88     -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000,
89     321240, 296592, 241692, 200376, -10000, -10000, -10000, -10000, -10000,
90     -10000, -10000, -10000, -10000, -10000, 348600, 294360, 253044, -10000,
91     -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000, -10000,
92     -10000, 308664, 233076, -10000, -10000, -10000, -10000, -10000, -10000,
93     -10000, -10000, -10000, -10000, -10000, -10000, 295896
94 };
95 
96 static const int ichoose2[5] = { 0, 0, 2, 6, 12 };
97 static int pairpoints, runpoints;		/* Globals from pairuns. */
98 
99 /*
100  * scorehand:
101  *	Score the given hand of n cards and the starter card.
102  *	n must be <= 4
103  *	crb is true if scoring crib
104  *	do_explain is true if must explain this hand
105  */
106 int
107 scorehand(CARD hand[], CARD starter, int n, bool crb, bool do_explain)
108 {
109 	int i, k;
110 	int score;
111 	bool flag;
112 	CARD h[(CINHAND + 1)];
113 	char buf[32];
114 
115 	explstr[0] = '\0';		/* initialize explanation */
116 	score = 0;
117 	flag = true;
118 	k = hand[0].suit;
119 	for (i = 0; i < n; i++) {	/* check for flush */
120 		flag = (flag && (hand[i].suit == k));
121 		if (hand[i].rank == JACK)	/* check for his nibs */
122 			if (hand[i].suit == starter.suit) {
123 				score++;
124 				if (do_explain)
125 					strcat(explstr, "His Nobs");
126 			}
127 		h[i] = hand[i];
128 	}
129 
130 	if (flag && n >= CINHAND) {
131 		if (do_explain && explstr[0] != '\0')
132 			strcat(explstr, ", ");
133 		if (starter.suit == k) {
134 			score += 5;
135 			if (do_explain)
136 				strcat(explstr, "Five-flush");
137 		} else
138 			if (!crb) {
139 				score += 4;
140 				if (do_explain && explstr[0] != '\0')
141 					strcat(explstr, ", Four-flush");
142 				else
143 					strcpy(explstr, "Four-flush");
144 			}
145 	}
146 	if (do_explain && explstr[0] != '\0')
147 		strcat(explstr, ", ");
148 	h[n] = starter;
149 	sorthand(h, n + 1);	/* sort by rank */
150 	i = 2 * fifteens(h, n + 1);
151 	score += i;
152 	if (do_explain) {
153 		if (i > 0) {
154 			sprintf(buf, "%d points in fifteens", i);
155 			strcat(explstr, buf);
156 		} else
157 			strcat(explstr, "No fifteens");
158 	}
159 	i = pairuns(h, n + 1);
160 	score += i;
161 	if (do_explain) {
162 		if (i > 0) {
163 			sprintf(buf, ", %d points in pairs, %d in runs",
164 			    pairpoints, runpoints);
165 			strcat(explstr, buf);
166 		} else
167 			strcat(explstr, ", No pairs/runs");
168 	}
169 	return (score);
170 }
171 
172 /*
173  * fifteens:
174  *	Return number of fifteens in hand of n cards
175  */
176 static int
177 fifteens(CARD hand[], int n)
178 {
179 	int *sp, *np;
180 	int i;
181 	CARD *endp;
182 	static int sums[15], nsums[15];
183 
184 	np = nsums;
185 	sp = sums;
186 	i = 16;
187 	while (--i) {
188 		*np++ = 0;
189 		*sp++ = 0;
190 	}
191 	for (endp = &hand[n]; hand < endp; hand++) {
192 		i = hand->rank + 1;
193 		if (i > 10)
194 			i = 10;
195 		np = &nsums[i];
196 		np[-1]++;	/* one way to make this */
197 		sp = sums;
198 		while (i < 15) {
199 			*np++ += *sp++;
200 			i++;
201 		}
202 		sp = sums;
203 		np = nsums;
204 		i = 16;
205 		while (--i)
206 			*sp++ = *np++;
207 	}
208 	return sums[14];
209 }
210 
211 /*
212  * pairuns returns the number of points in the n card sorted hand
213  * due to pairs and runs
214  * this routine only works if n is strictly less than 6
215  * sets the globals pairpoints and runpoints appropriately
216  */
217 static int
218 pairuns(CARD h[], int n)
219 {
220 	int i;
221 	int runlength, runmult, lastmult, curmult;
222 	int mult1, mult2, pair1, pair2;
223 	bool run;
224 
225 	run = true;
226 	runlength = 1;
227 	mult1 = 1;
228 	pair1 = -1;
229 	mult2 = 1;
230 	pair2 = -1;
231 	curmult = runmult = 1;
232 	for (i = 1; i < n; i++) {
233 		lastmult = curmult;
234 		if (h[i].rank == h[i - 1].rank) {
235 			if (pair1 < 0) {
236 				pair1 = h[i].rank;
237 				mult1 = curmult = 2;
238 			} else {
239 				if (h[i].rank == pair1) {
240 					curmult = ++mult1;
241 				} else {
242 					if (pair2 < 0) {
243 						pair2 = h[i].rank;
244 						mult2 = curmult = 2;
245 					} else {
246 						curmult = ++mult2;
247 					}
248 				}
249 			}
250 			if (i == (n - 1) && run) {
251 				runmult *= curmult;
252 			}
253 		} else {
254 			curmult = 1;
255 			if (h[i].rank == h[i - 1].rank + 1) {
256 				if (run) {
257 					++runlength;
258 				} else {
259 							/* only if old short */
260 					if (runlength < 3) {
261 						run = true;
262 						runlength = 2;
263 						runmult = 1;
264 					}
265 				}
266 				runmult *= lastmult;
267 			} else {
268 							/* if just ended */
269 				if (run)
270 					runmult *= lastmult;
271 				run = false;
272 			}
273 		}
274 	}
275 	pairpoints = ichoose2[mult1] + ichoose2[mult2];
276 	runpoints = (runlength >= 3 ? runlength * runmult : 0);
277 	return (pairpoints + runpoints);
278 }
279 
280 /*
281  * pegscore tells how many points crd would get if played after
282  * the n cards in tbl during pegging
283  */
284 int
285 pegscore(CARD crd, CARD tbl[], int n, int sum)
286 {
287 	bool got[RANKS];
288 	int i, j, scr;
289 	int k, lo, hi;
290 
291 	sum += VAL(crd.rank);
292 	if (sum > 31)
293 		return (-1);
294 	if (sum == 31 || sum == 15)
295 		scr = 2;
296 	else
297 		scr = 0;
298 	if (!n)
299 		return (scr);
300 	j = 1;
301 	while ((crd.rank == tbl[n - j].rank) && (n - j >= 0))
302 		++j;
303 	if (j > 1)
304 		return (scr + ichoose2[j]);
305 	if (n < 2)
306 		return (scr);
307 	lo = hi = crd.rank;
308 	for (i = 0; i < RANKS; i++)
309 		got[i] = false;
310 	got[crd.rank] = true;
311 	k = -1;
312 	for (i = n - 1; i >= 0; --i) {
313 		if (got[tbl[i].rank])
314 			break;
315 		got[tbl[i].rank] = true;
316 		if (tbl[i].rank < lo)
317 			lo = tbl[i].rank;
318 		if (tbl[i].rank > hi)
319 			hi = tbl[i].rank;
320 		for (j = lo; j <= hi; j++)
321 			if (!got[j])
322 				break;
323 		if (j > hi)
324 			k = hi - lo + 1;
325 	}
326 	if (k >= 3)
327 		return (scr + k);
328 	else
329 		return (scr);
330 }
331 
332 /*
333  * adjust takes a two card hand that will be put in the crib
334  * and returns an adjusted normalized score for the number of
335  * points such a crib will get.
336  */
337 int
338 adjust(CARD cb[])
339 {
340 	long scr;
341 	int i, c0, c1;
342 
343 	c0 = cb[0].rank;
344 	c1 = cb[1].rank;
345 	if (c0 > c1) {
346 		i = c0;
347 		c0 = c1;
348 		c1 = i;
349 	}
350 	if (cb[0].suit != cb[1].suit)
351 		scr = crbnescr[RANKS * c0 + c1];
352 	else
353 		scr = crbescr[RANKS * c0 + c1];
354 	if (scr <= 0) {
355 		printf("\nADJUST: internal error %d %d\n", c0, c1);
356 		exit(93);
357 	}
358 	return ((scr + 29400) / 58800);
359 }
360