841.cpp

/**
 *    author:   vulkan
 *    created:  03.08.2021 07:50:40 PM
**/
#include <bits/stdc++.h>

using namespace std;

void bfs(vector<vector<int>> &adj_list, int u, vector<bool> &visited) {
    int n = adj_list.size();
    queue<int> qu;
    qu.push(u);
    visited[u] = true;
    while (not qu.empty()) {
        int x = qu.front();
        qu.pop();
        for (int y : adj_list[x]) {
            if (not visited[y]) {
                visited[y] = true;
                qu.push(y);
            }
        }
    }
}

bool canVisitAllRooms(vector<vector<int>> &rooms) {
    int n = rooms.size();
    vector<bool> visited(n);
    bfs(rooms, 0, visited);

    return find(visited.begin(), visited.end(), false) == visited.end();
}

int main(int argc, char const *argv[]) {
    int n;
    cin >> n;
    vector<vector<int>> rooms(n);
    for (int i = 0; i <= n - 1; ++i) {
        int sz;
        cin >> sz;
        rooms[i] = vector<int>(sz);
        for (int j = 0; j <= sz - 1; ++j) {
            cin >> rooms[i][j];
        }
    }

    cout << canVisitAllRooms(rooms);

    return 0;
}