date and time created 82/05/11 14:53:55 by rrh

SCCS-vsn: games/backgammon/common_source/odds.c 1.1

diff --git a/usr/src/games/backgammon/common_source/odds.c b/usr/src/games/backgammon/common_source/odds.c
new file mode 100644 (file)
index 0000000..cce16bd
--- /dev/null
+++ b/usr/src/games/backgammon/common_source/odds.c
@@ -0,0 +1,78 @@
+static char sccsid[] = "       odds.c  1.1     82/05/11        ";
+
+#include "back.h"
+
+odds (r1,r2,val)
+register int   r1;
+int            r2, val;
+{
+       register int    i, j;
+
+       if (r1 == 0)  {
+               for (i = 0; i < 6; i++)  
+                       for (j = 0; j < 6; j++)
+                               table[i][j] = 0;
+               return;
+       } else  {
+               r1--;
+               if (r2-- == 0)
+                       for (i = 0; i < 6; i++)  {
+                               table[i][r1] += val;
+                               table[r1][i] += val;
+                       }
+               else  {
+                       table[r2][r1] += val;
+                       table[r1][r2] += val;
+               }
+       }
+}
+
+count ()  {
+       register int    i;
+       register int    j;
+       register int    total;
+
+       total = 0;
+       for (i = 0; i < 6; i++)
+               for (j = 0; j < 6; j++)
+                       total += table[i][j];
+       return (total);
+}
+\f
+canhit (i,c)
+int    i, c;
+
+{
+       register int    j, k, b;
+       int             a, d, diff, place, addon, menstuck;
+
+       if (c == 0)
+               odds (0,0,0);
+       if (board[i] > 0)  {
+               a = -1;
+               b = 25;
+       } else  {
+               a = 1;
+               b = 0;
+       }
+       place = abs (25-b-i);
+       menstuck = abs (board[b]);
+       for (j = b; j != i; j += a)  {
+               if (board[j]*a > 0)  {
+                       diff = abs(j-i);
+                       addon = place+((board[j]*a > 2 || j == b)? 5: 0);
+                       if ((j == b && menstuck == 1) &&
+                           (j != b && menstuck == 0))
+                               for (k = 1; k < diff; k++)
+                                       if (k < 7 && diff-k < 7 &&
+                                           (board[i+a*k]*a >= 0 ||
+                                           board[i+a*(diff-k)] >= 0))
+                                               odds (k,diff-k,addon);
+                       if ((j == b || menstuck < 2) && diff < 7)
+                               odds (diff,0,addon);
+               }
+               if (j == b && menstuck > 1)
+                       break;
+       }
+       return (count());
+}