//
// Created by 35395 on 2024/9/15.
//
#include<bits/stdc++.h>
using namespace std;
#define int long long
#define endl '\n'

const int N = 1e6 + 100;
int n,in[N];
int hh,tt,q[N];
vector<int> h[N];

void solve() {
    tt = 0, hh = 1;
    for(int i=0;i<=n;i++) h[i].clear(),in[i] = 0;
    cin >> n;
    for(int i=1;i<=n;i++){
        int l,r;
        cin >> l >> r;
        h[l].push_back(r+1);
        h[r+1].push_back(l);
        in[l]++, in[r+1]++;
    }
    for(int i=0;i<=n;i++) if(in[i] == 1) q[++tt] = i;
    while(tt >= hh){
        int u = q[hh++];
        for(auto v : h[u]){
            in[v]--;
            if(in[v] == 1) q[++tt] = v;
        }
    }
    if(tt == n + 1) cout << 1 << '\n';
    else cout << 0 << '\n';
}

signed main(){
    ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
    int T = 1;
    cin >> T;
    while(T--) solve();
    return 0;
}
/*
 *
1
4
1 1
2 3
1 4
4 4
6
1 6
5 5
2 3
4 6
3 4
5 6
 * */