BFS 三维迷宫

#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <queue>
using namespace std;
struct node{
    int x,y,z;
    int step;
}que,now,next1;
int l,r,c,ans,flag;
char mapp[50][50][50];
int vis[50][50][50];
int xx[]={0,0,0,0,1,-1};
int yy[]={0,0,1,-1,0,0};
int zz[]={1,-1,0,0,0,0};

void bfs(int sx,int sy,int sz){
    queue<node>ac;
    vis[sz][sx][sy]=1;
    que.x=sx;
    que.y=sy;
    que.z=sz;
    que.step=0;
    ac.push(que);
    while(!ac.empty()){
        int dx,dy,dz;
        now=ac.front();
        ac.pop();
        for(int i=0;i<6;i++){
            dx=next1.x=now.x+xx[i];
            dy=next1.y=now.y+yy[i];
            dz=next1.z=now.z+zz[i];
            next1.step=now.step+1;
            if(dx<0||dy<0||dz<0||dx>=r||dy>=c||dz>=l||mapp[dz][dx][dy]=='#')
                continue;
            if(mapp[dz][dx][dy]=='E'){
                ans=next1.step;
                flag=1;
                return ;
            }
            if(mapp[dz][dx][dy]=='.'&&!vis[dz][dx][dy]){
                vis[dz][dx][dy]=1;
                ac.push(next1);
            }
        }
    }
}

int main(){
    
    while(~scanf("%d%d%d",&l,&r,&c)&&l&&r&&c){
        memset(vis,0,sizeof vis);
        memset(mapp,0,sizeof mapp);
        flag=0;
        for(int i=0;i<l;i++){
            for(int j=0;j<r;j++){
                scanf("%s",mapp[i][j]);
            }
        }
        for(int i=0;i<l;i++){
            for(int j=0;j<r;j++){
                for(int k=0;k<c;k++){
                    if(mapp[i][j][k]=='S'){
                        bfs(j,k,i);
                    }
                }
            }
        }
        if(flag==1){
            printf("Escaped in %d minute(s).\n",ans);
        }
        
        else{
            printf("Trapped!\n");
        }
    }
    return 0;
}