xref: /original-bsd/games/cribbage/cards.c (revision 2301fdfb)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  */
17 
18 #ifndef lint
19 static char sccsid[] = "@(#)cards.c	5.3 (Berkeley) 06/18/88";
20 #endif /* not lint */
21 
22 #include	<stdio.h>
23 #include	"deck.h"
24 
25 
26 /*
27  * initialize a deck of cards to contain one of each type
28  */
29 
30 makedeck( d )
31 
32     CARD	d[];
33 {
34 	register  int		i, j, k;
35 	long			time();
36 
37 	i = time( (long *) 0 );
38 	i = ( (i&0xff) << 8 ) | ( (i >> 8)&0xff ) | 1;
39 	srand( i );
40 	k = 0;
41 	for( i = 0; i < RANKS; i++ )  {
42 	    for( j = 0; j < SUITS; j++ )  {
43 		d[k].suit = j;
44 		d[k++].rank = i;
45 	    }
46 	}
47 }
48 
49 
50 
51 /*
52  * given a deck of cards, shuffle it -- i.e. randomize it
53  * see Knuth, vol. 2, page 125
54  */
55 
56 shuffle( d )
57 
58     CARD	d[];
59 {
60 	register  int		j, k;
61 	CARD			c;
62 
63 	for( j = CARDS; j > 0; --j )  {
64 	    k = ( rand() >> 4 ) % j;		/* random 0 <= k < j */
65 	    c = d[j - 1];			/* exchange (j - 1) and k */
66 	    d[j - 1] = d[k];
67 	    d[k] = c;
68 	}
69 }
70 
71 
72 
73 /*
74  * return true if the two cards are equal...
75  */
76 
77 eq( a, b )
78 
79     CARD		a, b;
80 {
81 	return(  ( a.rank == b.rank )  &&  ( a.suit == b.suit )  );
82 }
83 
84 
85 
86 /*
87  * isone returns TRUE if a is in the set of cards b
88  */
89 
90 isone( a, b, n )
91 
92     CARD		a, b[];
93     int			n;
94 {
95 	register  int		i;
96 
97 	for( i = 0; i < n; i++ )  {
98 	    if(  eq( a, b[i] )   )  return( TRUE );
99 	}
100 	return( FALSE );
101 }
102 
103 
104 
105 /*
106  * remove the card a from the deck d of n cards
107  */
108 
109 remove( a, d, n )
110 
111     CARD		a, d[];
112     int			n;
113 {
114 	register  int		i, j;
115 
116 	j = 0;
117 	for( i = 0; i < n; i++ )  {
118 	    if(  !eq( a, d[i] )  )  d[j++] = d[i];
119 	}
120 	if(  j < n  )  d[j].suit = d[j].rank = EMPTY;
121 }
122 
123 
124 
125 /*
126  * sorthand:
127  *	Sort a hand of n cards
128  */
129 sorthand(h, n)
130 register CARD		h[];
131 int			n;
132 {
133 	register CARD		*cp, *endp;
134 	CARD			c;
135 
136 	for (endp = &h[n]; h < endp - 1; h++)
137 	    for (cp = h + 1; cp < endp; cp++)
138 		if ((cp->rank < h->rank) ||
139 		     (cp->rank == h->rank && cp->suit < h->suit)) {
140 		    c = *h;
141 		    *h = *cp;
142 		    *cp = c;
143 		}
144 }
145 
146