紫书6-12 uva810 筛子难题
bfs，注意状态判重有四个维度。#include<iostream>#include<string>#include<cstring>#include<queue>using namespace std;int m,n;int g[15][15];string gz[7];int vis[15][15][7][7];//记录状态 int a[4] = {-1,1,0,0};//NSWE
