minic/test/knight.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3
   4 void *calloc();
   5
   6 int N;
   7 int **b;
   8
   9 board()
  10 {
  11         int x;
  12         int y;
  13
  14         for (y=0; y<8; y++) {
  15                 for (x=0; x<8; x++)
  16                         printf(" %02d", b[x][y]);
  17                 printf("\n");
  18         }
  19         printf("\n");
  20         return 0;
  21 }
  22
  23 chk(int x, int y)
  24 {
  25         if (x < 0 || x > 7 || y < 0 || y > 7)
  26                 return 0;
  27         return b[x][y] == 0;
  28 }
  29
  30 go(int k, int x, int y)
  31 {
  32         int i;
  33         int j;
  34
  35         b[x][y] = k;
  36         if (k == 64) {
  37                 if (x != 2 && y != 0 && abs(x-2) + abs(y) == 3) {
  38                         board();
  39                         N++;
  40                         if (N == 10)
  41                                 exit(0);
  42                 }
  43         } else
  44                 for (i=-2; i<=2; i++)
  45                         for (j=-2; j<=2; j++)
  46                                 if (abs(i) + abs(j) == 3 && chk(x+i, y+j))
  47                                         go(k+1, x+i, y+j);
  48         b[x][y] = 0;
  49         return 0;
  50 }
  51
  52 main()
  53 {
  54         int i;
  55
  56         b = calloc(8, sizeof (int *));
  57         for (i=0; i<8; i++)
  58                 b[i] = calloc(8, sizeof (int));
  59         go(1, 2, 0);
  60 }