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

struct SCC {
    int n, group_num;
    std::vector<std::vector<int>> &g;
    std::vector<int> ids;
    SCC(std::vector<std::vector<int>> &_g) : n(_g.size()), g(_g), ids(n), group_num(0) {
        int now_ord = 0;
        std::vector<int> visited, low(n), ord(n, -1);
        visited.reserve(n);
        auto dfs = [&](auto self, int v) -> void {
            low[v] = ord[v] = now_ord++;
            visited.emplace_back(v);
            for(auto to : g[v]) {
                if (ord[to] == -1) {
                    self(self, to);
                    low[v] = std::min(low[v], low[to]);
                } else {
                    low[v] = std::min(low[v], ord[to]);
                }
            }
            if (low[v] == ord[v]) {
                while (true) {
                    int u = visited.back();
                    visited.pop_back();
                    ord[u] = n;
                    ids[u] = group_num;
                    if (u == v) break;
                }
                group_num++;
            }
        };
        for (int i = 0; i < n; i++) {
            if (ord[i] == -1) dfs(dfs, i);
        }
        for (auto& x : ids) {
            x = group_num - 1 - x;
        }
    }
    const int operator[](int p) const {
        assert(0 <= p && p < n);
        return ids[p];
    }
    int operator[](int p) { 
        assert(0 <= p && p < n);
        return ids[p];
    }
    std::vector<std::vector<int>> groups(){
        std::vector<int> counts(group_num);
        for (auto x : ids) counts[x]++;
        std::vector<std::vector<int>> groups(group_num);
        for (int i = 0; i < group_num; i++) {
            groups[i].reserve(counts[i]);
        }
        for (int i = 0; i < n; i++) {
            groups[ids[i]].emplace_back(i);
        }
        return groups;
    }
};

int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n;
	cin >> n;
	vector<vector<int>> g(n);
	for(int i = 0; i < n; i++){
		int m, j;
		cin >> m;
		while(m--){
			cin >> j;
			g[i].push_back(j - 1);
		}
	}
	
	SCC scc(g);
	auto G = scc.groups();
	vector<vector<int>> g2(G.size());
	vector<int> cnt(G.size());
	for(int i = 0; i < G.size(); i++){
		for(auto &&v : G[i]){
			for(auto &&u : g[v]){
				if(scc[v] == scc[u]) continue;
				g2[scc[v]].push_back(scc[u]);
				cnt[scc[u]]++;
			}
		}
	}
	if(cnt[scc[0]] != 0){
		cout << "No\n";
		return 0;
	}
	vector<bool> used(G.size());
	queue<int> que;
	que.emplace(scc[0]);
	while(!que.empty()){
		int v = que.front();
		if(que.size() >= 2){
			cout << "No\n";
			return 0;
		}
		used[v] = true;
		que.pop();
		for(auto &&u : g2[v]){
			cnt[u]--;
			if(cnt[u] == 0) que.emplace(u);
		}
	}
	cout << (count(used.begin(), used.end(), true) == G.size() ? "Yes" : "No") << '\n';
}