#include <bits/stdc++.h>
using namespace std;
using ll = long long;
// #define int ll
void solve()
{
    int n;
    cin >> n;
    vector<vector<int>> g(n + 1);
    for (int i = 1; i <= n; i++)
    {
        int l, r;
        cin >> l >> r;
        l--;
        g[l].push_back(r);
    }
    vector<int> vis(n + 1);
    int cnt = 0;
    auto dfs = [&](auto self, int u) -> void {
        if (vis[u] == 0)
        {
        	cerr<<u<<"\n";
            vis[u] = 1;
            cnt++;
            for (auto v : g[u])
            {
                self(self, v);
            }
        }
    };
    dfs(dfs, 0);
    if (cnt == n + 1)
    {
        cout << 1 << "\n";
    }
    else
    {
        cout << 0 << "\n";
    }
}
signed main()
{
    ios::sync_with_stdio(false), cin.tie(nullptr);
    int t = 1;
    cin >> t;
    while (t--)
    {
        solve();
    }
}