求高手帮我看看这段代码有啥问题
#include<stdio.h>#include<stdlib.h>
#define M 4
#define N 4
#define MaxSize 100
int mg1[M+2][N+2]={
{1,1,1,1,1,1},
{1,0,0,0,1,1},
{1,0,1,0,0,1},
{1,0,0,0,1,1},
{1,0,0,0,0,1},
{1,1,1,1,1,1}
};
struct
{
int i;
int j;
int pre;
}Qu[MaxSize];
int front=-1,rear=-1;
int minlen=0;
int num=1;
void print1(int front)
{
int k=front,j;
int ns=0;
do
{
j=k;
k=Qu[k].pre;
ns++;
} while(k!=-1);
if(num==1) minlen=ns;
if(ns==minlen)
{
ns=0;
k=front;
printf("第%d条最短路径(反向输出):\n",num++);
do
{
j=k;
printf("\t(%d,%d)",Qu[k].i,Qu[k].j);
k=Qu[k].pre;
if(++ns%5==0) printf("\n");
} while(k!=-1);
printf("\n");
}
}
void mgpath1(int x1,int y1,int x2,int y2)
{
int i,j,find=0,di,k;
rear++;
Qu[rear].i=x1;
Qu[rear].j=y1;
Qu[rear].pre=-1;
while(front!=rear)
{
front++;
for(di=0;di<4;di++)
{
switch(di)
{
case 0:i=Qu[front].i-1;j=Qu[front].j;break;
case 1:i=Qu[front].i;j=Qu[front].j+1;break;
case 2:i=Qu[front].i+1;j=Qu[front].j;break;
case 3:i=Qu[front].i;j=Qu[front].j-1;break;
}
if(i>0&&j>0&&mg1[i][j]==0&&(i!=Qu[Qu[front].pre].i||j!=Qu[Qu[front].pre].j))
{
rear++;
Qu[rear].i=i;
Qu[rear].j=j;
Qu[rear].pre=front;
}
}
}
for(k=0;k<=rear;k++)
{
if(Qu[k].i==x2&&Qu[k].j==y2)
{
find=1;
print1(k);
}
}
if(!find)
printf("不存在路径!\n");
}
void main()
{
printf("所有迷宫([1,1]->[4,4])最短路径\n");
mgpath1(1,1,M,N);
}