4.1cBSD/usr/src/games/cribbage/support.c
static char sccsid[] = " support.c 1.1 82/05/12 ";
#include <stdio.h>
#include "deck.h"
#include "cribbage.h"
#define NTV 10 /* number scores to test */
/* score to test reachability of, and order to test them in */
int tv[ NTV ] = { 8, 7, 9, 6, 11, 12, 13, 14, 10, 5 };
/*
* computer chooses what to play in pegging...
* only called if no playable card will score points
*/
cchose( h, n, s )
CARD h[];
int n;
int s;
{
register int i, j, l;
if( n <= 1 ) return( 0 );
if( s < 4 ) { /* try for good value */
if( ( j = anysumto(h, n, s, 4) ) >= 0 ) return( j );
if( ( j = anysumto(h, n, s, 3) ) >= 0 && s == 0 )
return( j );
}
if( s > 0 && s < 20 ) {
for( i = 1; i <= 10; i++ ) { /* try for retaliation to 31 */
if( ( j = anysumto(h, n, s, 21-i) ) >= 0 ) {
if( ( l = numofval(h, n, i) ) > 0 ) {
if( l > 1 || VAL( h[j].rank ) != i ) return( j );
}
}
}
}
if( s < 15 ) {
for( i = 0; i < NTV; i++ ) { /* for retaliation after 15 */
if( ( j = anysumto(h, n, s, tv[i]) ) >= 0 ) {
if( ( l = numofval(h, n, 15-tv[i]) ) > 0 ) {
if( l > 1 || VAL( h[j].rank ) != 15-tv[i] ) return( j );
}
}
}
}
j = -1;
for( i = n - 1; i >= 0; --i ) { /* remember: h is sorted */
l = s + VAL( h[i].rank );
if( l > 31 ) continue;
if( l != 5 && l != 10 && l != 21 ) {
j = i;
break;
}
}
if( j >= 0 ) return( j );
for( i = n - 1; i >= 0; --i ) {
l = s + VAL( h[i].rank );
if( l > 31 ) continue;
if( j < 0 ) j = i;
if( l != 5 && l != 21 ) {
j = i;
break;
}
}
return( j );
}
/*
* evaluate and score a player hand or crib
*/
plyrhand( hand, s )
CARD hand[];
char *s;
{
register int i, j;
BOOLEAN win;
printf( "Your %s is: ", s );
prhand( hand, CINHAND, TRUE );
printf( " [" );
printcard( turnover, TRUE );
printf( "]. How many points? " );
i = scorehand( hand, turnover, CINHAND, FALSE ); /* count */
if( ( j = number(0, 29) ) == 19 ) j = 0;
if( i != j ) {
if( i < j ) {
win = chkscr( &pscore, i );
printf( "It's really only %d points, I get %d.\n", i, 2 );
if( !win ) win = chkscr( &cscore, 2 );
}
else {
win = chkscr( &pscore, j );
printf( "You should have taken %d, not %d!\n", i, j );
}
if( explain ) {
printf( "Explanation: %s\n", expl );
}
}
else {
win = chkscr( &pscore, i );
}
return( win );
}
/*
* handle scoring and displaying the computers hand
*/
comphand( h, s )
CARD h[];
char *s;
{
register int j;
j = scorehand( h, turnover, CINHAND, FALSE );
printf( "My %s ( ", s );
prhand( h, CINHAND, TRUE );
printf( " [" );
printcard( turnover, TRUE );
printf( "] ) scores %d.\n", (j == 0 ? 19 : j) );
return( chkscr( &cscore, j ) );
}
/*
* add inc to scr and test for > glimit
*/
chkscr( scr, inc )
int *scr, inc;
{
return( ( (*scr += inc) >= glimit ? TRUE : FALSE ) );
}
/*
* cdiscard -- the computer figures out what is the best discard for
* the crib and puts the best two cards at the end
*/
cdiscard( mycrib )
BOOLEAN mycrib;
{
CARD d[ CARDS ], h[ FULLHAND ], cb[ 2 ];
register int i, j, k;
int nc, ns;
long sums[ 15 ];
static int undo1[15] = {0,0,0,0,0,1,1,1,1,2,2,2,3,3,4};
static int undo2[15] = {1,2,3,4,5,2,3,4,5,3,4,5,4,5,5};
makedeck( d );
nc = CARDS;
for( i = 0; i < knownum; i++ ) { /* get all other cards */
remove( known[i], d, nc-- );
}
for( i = 0; i < 15; i++ ) sums[i] = 0L;
ns = 0;
for( i = 0; i < (FULLHAND - 1); i++ ) {
cb[0] = chand[i];
for( j = i + 1; j < FULLHAND; j++ ) {
cb[1] = chand[j];
for( k = 0; k < FULLHAND; k++ ) h[k] = chand[k];
remove( chand[i], h, FULLHAND );
remove( chand[j], h, FULLHAND - 1 );
for( k = 0; k < nc; k++ ) {
sums[ns] += scorehand( h, d[k], CINHAND, TRUE );
if( mycrib ) sums[ns] += adjust( cb, d[k] );
else sums[ns] -= adjust( cb, d[k] );
}
++ns;
}
}
j = 0;
for( i = 1; i < 15; i++ ) if( sums[i] > sums[j] ) j = i;
for( k = 0; k < FULLHAND; k++ ) h[k] = chand[k];
remove( h[ undo1[j] ], chand, FULLHAND );
remove( h[ undo2[j] ], chand, FULLHAND - 1 );
chand[4] = h[ undo1[j] ];
chand[5] = h[ undo2[j] ];
}
/*
* returns true if some card in hand can be played without exceeding 31
*/
anymove( hand, n, sum )
CARD hand[];
int n;
int sum;
{
register int i, j;
if( n < 1 ) return( FALSE );
j = hand[0].rank;
for( i = 1; i < n; i++ ) {
if( hand[i].rank < j ) j = hand[i].rank;
}
return( sum + VAL( j ) <= 31 );
}
/*
* anysumto returns the index (0 <= i < n) of the card in hand that brings
* the s up to t, or -1 if there is none
*/
anysumto( hand, n, s, t )
CARD hand[];
int n;
int s, t;
{
register int i;
for( i = 0; i < n; i++ ) {
if( s + VAL( hand[i].rank ) == t ) return( i );
}
return( -1 );
}
/*
* return the number of cards in h having the given rank value
*/
numofval( h, n, v )
CARD h[];
int n;
int v;
{
register int i, j;
j = 0;
for( i = 0; i < n; i++ ) {
if( VAL( h[i].rank ) == v ) ++j;
}
return( j );
}
/*
* makeknown remembers all n cards in h for future recall
*/
makeknown( h, n )
CARD h[];
int n;
{
register int i;
for( i = 0; i < n; i++ ) {
known[ knownum++ ] = h[i];
}
}