제출 #1150473

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1150473		bilgun	Newspapers (CEOI21_newspapers)	C++20	4 / 100	1 ms	328 KiB

newspapers

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

long long n, m, sum = 0;
vector<vector<long long>> g;
vector<long long> col, more;
int yno = 0;
int ans;

void dfs(int node, int dest, int &ways, vector<bool>vis) {
	vis[node] = true;
	if( node == dest && node ) ways++;
		for( int i = 0; i < g[node].size(); i++) {
		    if( !vis[i]){
		        dfs( i, dest, ways, vis);
		    }
		    else if( vis[i] == true && i == node){
		        ways++;
		        return;
		    }
		    
		}
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	cin >> n >> m;
	g.resize(n + 1);
	col.resize(n + 1); 
	if( m != n - 1) {cout << "NO"; return 0;}
	else if( n == 1){
	    cout << "YES" << endl;
        cout << 2 << endl;
        cout << "1 1" << endl;
        return 0;
	}
	else if( n == 2 ){
	    cout << "YES" << endl;
        cout << 2 << endl;
        cout << "1 1" << endl;
        return 0;
	}

	for( int i = 1; i <= m; i++)
	{
		long long a, b;
		cin >> a >> b;
		g[a].push_back(b);
		g[b].push_back(a);
	}

	for( int i = 1; i <= n; i++)
	{
		for( int j = i + 1; i <= n; i++) {
		    int ways = 0;
			vector<bool> vis(1005, false);
			dfs(i, j, ways, vis);
			if( ways > 1 ) {yno = 1; break;}
			else{ ans = i; }
		}
	}
	
	if( !yno ) {cout << "YES" << endl;
	    cout << 2 << endl;
	    cout << ans << ' ' << ans;
	}
	else cout << "NO" << endl;

	return 0;
}

• Subtask 1: 0 / 12
• Subtask 2: 4 / 8
• Subtask 3: 0 / 80