题目传送门

#include <iostream>
#include <algorithm>
#include <bits/stdc++.h>
using namespace std;
//This c++ file is for solving problem:
int n,sx,sy,ex,ey;
int mp[1100][1100];
bool vis[1100][1100];
int dx[4]={1,-1,0,0},dy[4]={0,0,1,-1};
struct node{
	int x,y,step;
};
queue<node> q;
void bfs(){
	q.push(node{sx,sy,0});
	vis[sx][sy]=1;
	while(!q.empty()){
		node t=q.front();
		q.pop();
		if(t.x==ex&&t.y==ey){
			cout<<t.step;
			return;
		}
		for(int i=0;i<4;i++){
			int x=t.x+dx[i];
			int y=t.y+dy[i];
			if(x>=1&&x<=n&&y>=1&&y<=n&&vis[x][y]==0){
				q.push(node{x,y,t.step+1});
				vis[x][y]=1;
			}
		}
	}
}
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		string m;
		cin>>m;
		for(int j=0;j<n;j++){
			mp[i][j+1]=m[i]-'0';
		}
	}
	cin>>sx>>sy>>ex>>ey;
	bfs();
	return 0;
}