Submission

Score: 100

User: kavin8888

Problemset: ตั้งฐานทัพ

Language: cpp

Time: 0.021 second

Submitted On: 2025-10-30 08:28:39

#include<bits/stdc++.h>
using namespace std;
#define spps cin.tie(0)->sync_with_stdio(false);
#define MAX_N 750
#define pii pair<int,int>
vector<string> v(MAX_N);
vector<vector<bool>> chk(MAX_N,vector<bool>(MAX_N,false));
int n,m;
bool valid(int row,int col)
{
	return 0<=row && row<n && 0<=col && col<m;
}
int run(int row,int col)
{
	queue<pii> q;
	q.push({row,col});
	chk[row][col]=true;
	int cnt=0;
	while(!q.empty())
	{
		auto [x,y]=q.front();
		q.pop();
		cnt++;
		for(int i=x-1;i<=x+1;i++)
		{
			for(int j=y-1;j<=y+1;j++)
			{
				if(valid(i,j) && v[i][j]=='.' && !chk[i][j])
				{
					chk[i][j]=true;
					q.push({i,j});
				}
			}
		}
	}
	return cnt;
}
int main()
{
	cin>>m>>n;
	for(int i=0;i<n;i++)
	{
		cin>>v[i];
	}
	int ans=0;
	for(int i=0;i<n;i++)
	{
		for(int j=0;j<m;j++)
		{
			if(v[i][j]=='.' && !chk[i][j])
			{
				ans=max(ans,run(i,j));
			}
		}
	}
	cout<<ans<<'\n';
	return 0;
}