#include <bits/stdc++.h>
#define int long long
#define N 1000005

using namespace std;

int n,T;
vector<int>E[N];
int min(int x,int y){
    return x<y ? x : y;
}

int max(int x,int y){
    return x>y ? x : y;
}


int read(){
    int i=0;char ch;
    while(!isdigit(ch)){
        ch=getchar();
    }
    while(isdigit(ch)){
        i=(i<<3)+(i<<1)+(ch^48);
        ch=getchar();
    }
    return i;
}


void Solve(){
    n=read();
    for(int i=1;i<=n;i++){
        E[i].clear();
    }
    int x,y;
    for(int i=1;i<=n;i++){
        x=read();
        y=read();
        E[x].push_back(y);
    }
    int ju=0;
    for(int i=1;i<=n;i++){
        sort(E[i].begin(),E[i].end());
    }
    for(int i=1;i<=n;i++){
        int tmp=E[i][0];
        ju=0;
        if(E[i].size()==1)ju=1;
        for(int j=1;j<E[i].size();j++){
            if(E[i][j]>E[i][0]){
                E[E[i][0]+1].push_back(E[i][j]);
                ju=1;
            }
        }
        if(!ju){
            cout<<0<<endl;
            return;
        }
    }
    cout<<1<<endl;
    return;
}


signed main()
{
    //cin.tie(0), cout.tie(0), ios::sync_with_stdio(0);
    T=read();
    for(int i=1;i<=T;++i){
        Solve();
    }
    return 0;
}