void print_board(int board[B][B])
{
int i, j;
printf(" a b c d e f g h \n");
printf(" -----------------\n");
for (i = 1; i <= 8; i++) {
printf("%d|", i);
for (j = 1; j <= 8; j++) {
printf("%2d", board[i][j]);
}
printf(" |\n");
}
printf(" -----------------\n");
}