尽最大能力优化了，9和10还是超时

#include <bits/stdc++.h>
using namespace std;
long long mp[3000][3000],vis[3000][3000],book[9999][9999],n,m;
struct node {int x;int y;};
queue<node> q;
int dx[] = {0, 1, 0, -1};
int dy[] = {1, 0, -1, 0};
int main() {
    char p;
	cin >> n >> m;
    for(int i=1;i<=n;i++){
    	for(int j=1;j<=n;j++){
        	cin>>p;
        	mp[i][j]=p-'0';
    	}	
	}
	for(int j=1;j<=m;j++){
		long long x,y,s=1;
		cin >> x >> y;
		if(book[x][y] !=0 ){
			cout << book[x][y] << endl; 
		}else{
			q.push((node){x,y});
			vis[x][y] = j+8888;
			while(!q.empty()){
				node cur = q.front();q.pop();
				for(int i=0;i<4;i++){
					int tx = cur.x + dx[i];
					int ty = cur.y + dy[i];
					if(tx>=1&&tx<=n && ty>=1&&ty<=n && vis[tx][ty]!=j+8888 && mp[cur.x][cur.y]!=mp[tx][ty]){
						q.push((node){tx,ty});
						vis[tx][ty]=j+8888;
						s++;
					}
				}
			}
			book[x][y] = s;
			cout << s << endl;
		}
	}
    return 0;
}