1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 static char sccsid[] = "@(#)odds.c	5.4 (Berkeley) 06/01/90";
10 #endif /* not lint */
11 
12 #include "back.h"
13 
14 odds (r1,r2,val)
15 register int	r1;
16 int		r2, val;
17 {
18 	register int	i, j;
19 
20 	if (r1 == 0)  {
21 		for (i = 0; i < 6; i++)
22 			for (j = 0; j < 6; j++)
23 				table[i][j] = 0;
24 		return;
25 	} else  {
26 		r1--;
27 		if (r2-- == 0)
28 			for (i = 0; i < 6; i++)  {
29 				table[i][r1] += val;
30 				table[r1][i] += val;
31 			}
32 		else  {
33 			table[r2][r1] += val;
34 			table[r1][r2] += val;
35 		}
36 	}
37 }
38 
39 count ()  {
40 	register int	i;
41 	register int	j;
42 	register int	total;
43 
44 	total = 0;
45 	for (i = 0; i < 6; i++)
46 		for (j = 0; j < 6; j++)
47 			total += table[i][j];
48 	return (total);
49 }
50 
51 canhit (i,c)
52 int	i, c;
53 
54 {
55 	register int	j, k, b;
56 	int		a, d, diff, place, addon, menstuck;
57 
58 	if (c == 0)
59 		odds (0,0,0);
60 	if (board[i] > 0)  {
61 		a = -1;
62 		b = 25;
63 	} else  {
64 		a = 1;
65 		b = 0;
66 	}
67 	place = abs (25-b-i);
68 	menstuck = abs (board[b]);
69 	for (j = b; j != i; j += a)  {
70 		if (board[j]*a > 0)  {
71 			diff = abs(j-i);
72 			addon = place+((board[j]*a > 2 || j == b)? 5: 0);
73 			if ((j == b && menstuck == 1) &&
74 			    (j != b && menstuck == 0))
75 				for (k = 1; k < diff; k++)
76 					if (k < 7 && diff-k < 7 &&
77 					    (board[i+a*k]*a >= 0 ||
78 					    board[i+a*(diff-k)] >= 0))
79 						odds (k,diff-k,addon);
80 			if ((j == b || menstuck < 2) && diff < 7)
81 				odds (diff,0,addon);
82 		}
83 		if (j == b && menstuck > 1)
84 			break;
85 	}
86 	return (count());
87 }
88