P1605 迷宫

很经典的一道DFS题

#include "bits/stdc++.h"
using namespace std;
int a[6][6],ans;
int n,m,t;
bool vis[6][6];//判断是否经历过
int sx,sy,fx,fy;
int mx[4]={0,0,-1,1};
int my[4]={-1,1,0,0};方向数组
void out(int x,int y){
    if (x==fx&&y==fy){
        ans++;
        return;
    }
    vis[x][y]= true;//标记
    for(int i=0;i<=3;i++){
        if (a[x+mx[i]][y+my[i]]==0&&vis[x+mx[i]][y+my[i]]==0){
            int x1,y1;
            x1=x+mx[i];
            y1=y+my[i];
            if (x1>=1&&x1<=n&&y1>=1&&y1<=m){
                out(x1,y1);
                vis[x1][y1]= false;//回溯
            }
        }
    }
}
int main(){
    cin>>n>>m>>t;cin>>sx>>sy>>fx>>fy;
    for (int i = 1; i <= t; ++i) {
        int x,y;cin>>x>>y;
        a[x][y]=1;
    }
    out(sx,sy);
    cout<<ans;
    return 0;
}