#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n; cin >> n;
	vector to(n, vector<int>());
	rep(i, n) {
		int m; cin >> m;
		rep(j, m) {
			int a; cin >> a;
			a--;
			to[i].push_back(a);
		}
	}
	vector<bool>dp(n);
	dp[0] = true;
	queue<int> q;
	q.push(0);
	while (!q.empty()) {
		auto p = q.front();
		q.pop();
		rep(i, to[p].size()) {
			if (dp[to[p][i]])continue;
			dp[to[p][i]] = true;
			q.push(to[p][i]);
		}
	}
	bool chk = true;
	rep(i, n)if (!dp[i])chk = false;
	cout << (chk ? "Yes" : "No") << endl;
	return 0;
}