Submission #5425374

---

Source Code Expand

#include <iostream>
#include <string>
#include <functional>
#include <algorithm>
#include <vector>
#include <queue>
#include <math.h>
#include <map>

using namespace std;
using ll = long long;

int main()
{
	int n, m;
	cin >> n >> m;

	map<int, vector <int> > l2m;
	map<int, vector <int> > adj;

	for (int i = 0; i < n; ++i)
	{
		int k;
		cin >> k;
		k--;

		for (int j = 0; j < k; ++j)
		{
			int l;
			cin >> l;
			l--;
			l2m[j].push_back(i);

			for (auto hito: l2m[j])
			{
				adj[hito].push_back(i);
				adj[i].push_back(hito);
			}
		}
	}

	queue<int>q;
	vector<bool>cat(n, false);


	q.push(0);
	cat[0] = true;

	while (!q.empty())
	{
		int oya = q.front();
		q.pop();

		for (int child : adj[oya])
		{
			if (!cat[child])
			{
				q.push(child);
				cat[child] = true;
			}
		}
	}

	bool flag = true;

	for (bool isadj : cat)
		flag = flag && isadj;

	if (flag)
		cout << "YES" << endl;
	else
		cout << "NO" << endl;
	
	return 0;
}

Submission Info

Judge Result