UVA 532 Dungeon Master

#include<stdio.h>
#include<string.h>
int a[40][40][40],vis[40][40][40];
int qx[30000],qy[30000],ql[30000],dis[30000];
int dx[]={-1,1,0,0},dy[]={0,0,-1,1};
char b[40];
int main()
{
int i,j,k,L,R,C;
int front,rear,newx,newy,newl,x,y,l;
while(1)
{
scanf("%d%d%d",&L,&R,&C);
if(L==0)
break;
memset(a,0,sizeof(a));
for(i=1;i<=L;i++)
{
for(j=1;j<=R;j++)
{
scanf("%s",b+1);
for(k=1;k<=C;k++)
{
if(b[k]=='.')
a[i][j][k]=1;
else if(b[k]=='S')
{
a[i][j][k]=2;
x=j;
y=k;
l=i;
}
else if(b[k]=='E')
a[i][j][k]=3;
}
}
}
front=rear=0;
memset(vis,0,sizeof(vis));
ql[rear]=l;
qx[rear]=x;
qy[rear]=y;
vis[l][x][y]=1;
dis[rear]=0;
rear++;
while(front<rear)
{
l=ql[front];
x=qx[front];
y=qy[front];
if(a[l][x][y]==3)
break;
front++;
for(i=0;i<4;i++)
{
newx=x+dx[i];
newy=y+dy[i];
if(a[l][newx][newy]&&!vis[l][newx][newy])
{
vis[l][newx][newy]=1;
ql[rear]=l;
qx[rear]=newx;
qy[rear]=newy;
dis[rear]=dis[front-1]+1;
rear++;
}
}
for(i=-1;i<=1;i+=2)
{
newl=l+i;
if(a[newl][x][y]&&!vis[newl][x][y])
{
vis[newl][x][y]=1;
ql[rear]=newl;
qx[rear]=x;
qy[rear]=y;
dis[rear]=dis[front-1]+1;
rear++;
}
}
}
if(a[l][x][y]==3)
printf("Escaped in %d minute(s).\n",dis[front]);
else
printf("Trapped!\n");
}
return 0;
}