Submission

Score: 100

User: kimza

Problemset: เกาะที่ใหญ่ที่สุด

Language: cpp

Time: 0.003 second

Submitted On: 2026-03-06 18:59:37

#include <bits/stdc++.h>
using namespace std;
int main(){
    cin.tie(nullptr)->sync_with_stdio(false);
    int n,m;
    cin >> n >> m;
    vector<string> mp;
    for(int i=0;i<n;i++){
        string s;
        cin >> s; 
        mp.push_back(s);
    }
    int maxcnt = 0;
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            if(mp[i][j]=='1'){
                int cnt = 0;
                queue<pair<int,int>> q;
                q.push({i,j});
                mp[i][j]='0';
                cnt++;
                while(!q.empty()){
                    int y = q.front().first;
                    int x = q.front().second;
                    q.pop();
                    if(y+1<n && mp[y+1][x]=='1'){
                        q.push({y+1,x});
                        mp[y+1][x]='0';
                        cnt++;
                    }
                    if(x+1<m && mp[y][x+1]=='1'){
                        q.push({y,x+1});
                        mp[y][x+1]='0';
                        cnt++;
                    }
                    if(y-1>=0 && mp[y-1][x]=='1'){
                        q.push({y-1,x});
                        mp[y-1][x]='0';
                        cnt++;
                    }
                    if(x-1>=0 && mp[y][x-1]=='1'){
                        q.push({y,x-1});
                        mp[y][x-1]='0';
                        cnt++;
                    }
                }
                if(cnt > maxcnt) maxcnt = cnt;
            }
        }
    }
    cout << maxcnt;
    return 0;
}