#include<bits/stdc++.h>
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define print(a) for(auto i:a)cout<<i<<" ";cout<<endl;
#define print1(a) for(int i=1;i<a.size();i++)cout<<a[i]<<" ";cout<<endl;
#define scan(a) for(auto &i:a)cin>>i;
#define scan1(a) for(int i=1;i<a.size();i++)cin>>a[i];
using namespace std;
#define lowbit(x) (x&(-x))
#define ull unsigned long long
#define int long long
#define endl "\n"
#define pb push_back
#define fi first
#define se second
typedef pair<int,int>PII;
typedef pair<PII,int>pii;
const int mod=1e9+7;
int T,n,k,m;
string s;
priority_queue<int,vector<int>,greater<int>>q[1000110];

void solve()
{
    cin>>n;
    for(int i=1;i<=n;i++){
        int a,b;cin>>a>>b;
        q[a].push(b);
    }
    for(int i=1;i<=n;i++){
        while(!q[i].empty()&&q[i].top()<i)q[i].pop();
        if(q[i].empty()){
            cout<<0<<endl;return ;
        }
        int t=q[i].top()+1;q[i].pop();
        if(q[i].size()>q[t].size())swap(q[i],q[t]);
        while(q[i].size()){
            q[t].push(q[i].top());q[i].pop();
        }
    }
    cout<<1<<endl;
}

signed main()
{
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    T=1;
    cin>>T;
    while(T--)solve();
}