#include <bits/stdc++.h>   using namespace std;   const long long int N = 3e5 + 10, N2 = 2e5, delta = 10499, mod = 1e9 + 7,                       oo = 1e18, LOG = 20, SQ = 300;   const long double PI = 3.141592653589793;   pair<pair<long long int, long long int>, long long int> p[N];   int32_t main() {     ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);     long long int t;     cin >> t;     while (t--) {       long long int n;       cin >> n;       for (long long int i = 0; i < 2 * n - 1; i++) {         long long int x, y;         cin >> x >> y;         p[i] = {{x, y}, i};       }       cout <<  YES n ;       sort(p, p + 2 * n - 1);       for (long long int i = 0; i < 2 * n - 2; i += 2) {         if (p[i].first.second < p[i + 1].first.second)           cout << p[i + 1].second + 1 <<    ;         else           cout << p[i].second + 1 <<    ;       }       cout << p[2 * n - 2].second + 1 <<   n ;     }     return 0;   }   