Submission

Score: 0

User: navysrimuang

Problemset: เกาะที่ใหญ่ที่สุด

Language: cpp

Time: 0.004 second

Submitted On: 2026-03-14 11:39:42

#include<bits/stdc++.h>
using namespace std;

int n,m;
int mx = INT_MIN;
int sz;
bool grid[200][200];
bool vis[200][200];
int dx[] = {1,0,-1,0};
int dy[] = {0,1,0,-1};

int main(){
	cin.tie(0)->sync_with_stdio(0);
	cin >> n >> m;
	for(int i = 1;i<=n;i++){
		for(int j = 1;j<=m;j++){
			char c; cin >> c;
			if(c == '1') grid[i][j] = 1;
		}
	}

	for(int i = 1;i<=n;i++){
		for(int j = 1;j<=m;j++){
			if(!vis[i][j]){
				vis[i][j] = 1;
				sz = 0;
				stack<pair<int,int>> st;
				st.push({i,j});
				while(st.size()){
					auto [x,y] = st.top();
					st.pop();
					for(int i = 0;i<4;i++){
						int xx = x+dx[i]; int yy = y+dy[i];
						if(xx > n || yy > m || xx <= 0 || yy <= 0  || !grid[xx][yy] || vis[xx][yy]) continue;
						vis[xx][yy] = 1;
						sz++;
						st.push({xx,yy});
					}
				}
				mx = max(mx,sz);
			}
		}
	}
	
	cout << mx << "\n";
	return 0;
}