90分最后超时求调！！！

#include <bits/stdc++.h>
using namespace std;
#define int long long
int n,m;
#define N 1010
int a[N][N];
int vis[N][N]={};
int bfs(int x,int y){
	
	int s=1;
	bool is[N][N]={};
	vector<pair<int,int>> v;
	is[x][y]=true;
	v.push_back({x,y});
	queue<pair<int,int>> q;
	q.push({x,y});
	while(!q.empty()){
		pair<int,int> top=q.front();
		q.pop();
		if(top.second+1<n&&a[top.first][top.second]==!a[top.first][top.second+1])
		if(is[top.first][top.second+1]==false){
			q.push({top.first,top.second+1});
			s++;
			is[top.first][top.second+1]=true;
			v.push_back({top.first,top.second+1});
		}
		if(top.first+1<n&&a[top.first][top.second]==!a[top.first+1][top.second])
		if(is[top.first+1][top.second]==false){
			q.push({top.first+1,top.second});
			s++;
			is[top.first+1][top.second]=true;
			v.push_back({top.first+1,top.second});
		}
		if(top.second-1>=0&&a[top.first][top.second]==!a[top.first][top.second-1])
		if(is[top.first][top.second-1]==false){
			q.push({top.first,top.second-1}); 
			s++;
			is[top.first][top.second-1]=true;
			v.push_back({top.first,top.second-1});
		}
		if(top.first-1>=0&&a[top.first][top.second]==!a[top.first-1][top.second])
		if(is[top.first-1][top.second]==false){
			q.push({top.first-1,top.second});
			s++;
			is[top.first-1][top.second]=true;
			v.push_back({top.first-1,top.second});
		}
	}
	for(int i=0;i<v.size();i++){
		vis[v[i].first][v[i].second]=s;
	}
	return s;
}
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	cin>>n>>m;
	char ppppp;
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			cin>>ppppp;a[i][j]=ppppp-'0';
		}
	}
	int x,y;
	while(m--){
		cin>>x>>y;
		x--,y--;
		if(vis[x][y]!=0)cout<<vis[x][y]<<"\n";
		else cout<<bfs(x,y)<<"\n";
	}
}