usr/src/games/cribbage/cards.c

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)cards.c     5.5 (Berkeley) 2/28/91";
#endif /* not lint */

#include        <stdio.h>
#include        "deck.h"


/*
 * initialize a deck of cards to contain one of each type
 */

makedeck( d )

    CARD        d[];
{
        register  int           i, j, k;
        long                    time();

        i = time( (long *) 0 );
        i = ( (i&0xff) << 8 ) | ( (i >> 8)&0xff ) | 1;
        srand( i );
        k = 0;
        for( i = 0; i < RANKS; i++ )  {
            for( j = 0; j < SUITS; j++ )  {
                d[k].suit = j;
                d[k++].rank = i;
            }
        }
}


/*
 * given a deck of cards, shuffle it -- i.e. randomize it
 * see Knuth, vol. 2, page 125
 */

shuffle( d )

    CARD        d[];
{
        register  int           j, k;
        CARD                    c;

        for( j = CARDS; j > 0; --j )  {
            k = ( rand() >> 4 ) % j;            /* random 0 <= k < j */
            c = d[j - 1];                       /* exchange (j - 1) and k */
            d[j - 1] = d[k];
            d[k] = c;
        }
}


/*
 * return true if the two cards are equal...
 */

eq( a, b )

    CARD                a, b;
{
        return(  ( a.rank == b.rank )  &&  ( a.suit == b.suit )  );
}


/*
 * isone returns TRUE if a is in the set of cards b
 */

isone( a, b, n )

    CARD                a, b[];
    int                 n;
{
        register  int           i;

        for( i = 0; i < n; i++ )  {
            if(  eq( a, b[i] )   )  return( TRUE );
        }
        return( FALSE );
}


/*
 * remove the card a from the deck d of n cards
 */

cremove( a, d, n )

    CARD                a, d[];
    int                 n;
{
        register  int           i, j;

        j = 0;
        for( i = 0; i < n; i++ )  {
            if(  !eq( a, d[i] )  )  d[j++] = d[i];
        }
        if(  j < n  )  d[j].suit = d[j].rank = EMPTY;
}


/*
 * sorthand:
 *      Sort a hand of n cards
 */
sorthand(h, n)
register CARD           h[];
int                     n;
{
        register CARD           *cp, *endp;
        CARD                    c;

        for (endp = &h[n]; h < endp - 1; h++)
            for (cp = h + 1; cp < endp; cp++)
                if ((cp->rank < h->rank) ||
                     (cp->rank == h->rank && cp->suit < h->suit)) {
                    c = *h;
                    *h = *cp;
                    *cp = c;
                }
}