#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxN = 1e6 + 5;
int fa[maxN];
int find(int x)
{
    if (fa[x] == x)
    {
        return x;
    }
    else
    {
        return fa[x] = find(fa[x]);
    }
}
bool unite(int x, int y)
{
    int xf = find(x), yf = find(y);
    if (xf == yf)
    {
        return true;
    }
    else
    {
        fa[yf] = xf;
        return false;
    }
}
void EachT()
{
    for (int i = 0; i < maxN; i++)
    {
        fa[i] = i;
    }
    int n;
    cin >> n;
    int ans = 1;
    for (int i = 0; i < n; i++)
    {
        int a, b;
        cin >> a >> b;
        if (unite(a, b + 1))
        {
            ans = 0;
        }
    }
    cout << ans << endl;
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    int t;
    cin >> t;
    while (t--)
    {
        EachT();
    }
    return 0;
}