c语言迷宫问题，以一个m×n的长方阵表示迷宫，0和1分别表示迷宫中的通路和障碍。

#define?STACK_SIZE?1000

#define?TRUE?1

#define?FALSE?0

#include?<stdio.h>

short?DIRECTION_UP?=?1;

short?DIRECTION_RIGHT?=?1?<<?1;

short?DIRECTION_DOWN?=?1?<<?2;

short?DIRECTION_LEFT?=?1?<<?3;

short?ALL_DIRECTIONS?=?DIRECTION_UP?|?DIRECTION_RIGHT?|?DIRECTION_DOWN?|?DIRECTION_LEFT;

typedef?struct?{

int?x;

int?y;

short?directions;

}?Cell;

typedef?struct?{

Cell?elem[STACK_SIZE];

int?top;

}?Stack;

void?initStack(Stack?*s)?{

s->top?=?-1;

}

int?isEmpty(Stack?*s)?{

return?(s->top?==?-1TRUE?:?FALSE);

}

void?push(Stack?*s,?Cell?e)?{

s->top++;

s->elem[s->top]?=?e;

}

void?pop(Stack?*s,?Cell?*e)?{

*e?=?s->elem[s->top];

s->top--;

}

int?hasDirection(Cell?*e,?short?d)?{

return?(e->directions?&?d)?!=?01?:?0;

}

void?removeDirection(Cell?*e,?short?d)?{

e->directions?=?e->directions?&?(~d);

}

int?main()?{

int?i,?j;

int?m,?n;

int?entranceX,?entranceY,?exitX,?exitY;

scanf("%d?%d",?&m,?&n);

short?a[m][n];

short?visited[m][n];

for?(i?=?0;?i?<?m;?i++)?{

for?(j?=?0;?j?<?n;?j++)?{

scanf("%d",?&a[i][j]);

visited[i][j]?=?0;

}

}

scanf("%d?%d?%d?%d",?&entranceX,?&entranceY,?&exitX,?&exitY);

Stack?steps;

initStack(&steps);

Cell?e;

e.y?=?entranceX;

e.x?=?entranceY;

e.directions?=?ALL_DIRECTIONS;

push(&steps,?e);

visited[entranceX][entranceY]?=?1;

while?(!isEmpty(&steps))?{

pop(&steps,?&e);

if?(e.x?==?exitX?&&?e.y?==?exitY)?{

push(&steps,?e);

break;

}

if?(e.x?>?0?&&?hasDirection(&e,?DIRECTION_UP)?&&?a[e.x?-?1][e.y]?==?0?&&?!visited[e.x?-?1][e.y])?{

removeDirection(&e,?DIRECTION_UP);

push(&steps,?e);

e.x--;

e.directions?=?ALL_DIRECTIONS;

removeDirection(&e,?DIRECTION_DOWN);

push(&steps,?e);

visited[e.x][e.y]?=?1;

}?else?if?(e.y?<?n?-?1?&&?hasDirection(&e,?DIRECTION_RIGHT)?&&?a[e.x][e.y?+?1]?==?0?&&?!visited[e.x][e.y?+?1])?{

removeDirection(&e,?DIRECTION_RIGHT);

push(&steps,?e);

e.y++;

e.directions?=?ALL_DIRECTIONS;

removeDirection(&e,?DIRECTION_LEFT);

push(&steps,?e);

visited[e.x][e.y]?=?1;

}?else?if?(e.x?<?m?-?1?&&?hasDirection(&e,?DIRECTION_DOWN)

&&?a[e.x?+?1][e.y]?==?0?&&?!visited[e.x?+?1][e.y])?{

removeDirection(&e,?DIRECTION_DOWN);

push(&steps,?e);

e.x++;

e.directions?=?ALL_DIRECTIONS;

removeDirection(&e,?DIRECTION_UP);

push(&steps,?e);

visited[e.x][e.y]?=?1;

}?else?if?(e.y?>?0?&&?hasDirection(&e,?DIRECTION_LEFT)

&&?a[e.x][e.y?-?1]?==?0?&&?!visited[e.x][e.y?-?1])?{

removeDirection(&e,?DIRECTION_LEFT);

push(&steps,?e);

e.y--;

e.directions?=?ALL_DIRECTIONS;

removeDirection(&e,?DIRECTION_RIGHT);

push(&steps,?e);

visited[e.x][e.y]?=?1;

}

}

if?(isEmpty(&steps))?{

printf("No");

}?else?{

printf("Yes");

}

return?0;

}