func_code_string: #include <bits/stdc++.h>   using namespace std;   int arr[10001];   int main() {     int test;     cin >> test;     while (test--) {       int n;       cin >> n;       vector<int> ans1, ans2;       for (int i = 0; i < 2 * n; i++) cin >> arr[i];       vector<pair<int, int> > vp;       for (int i = 0; i < 2 * n; i++) {         if (arr[i] % 2 == 0)           ans2.push_back(i + 1);         else           ans1.push_back(i + 1);       }       for (int i = 1; i < ans2.size(); i += 2)         vp.push_back({ans2[i], ans2[i - 1]});       for (int i = 1; i < ans1.size(); i += 2)         vp.push_back({ans1[i], ans1[i - 1]});       for (int i = 0; i < n - 1; i++)         cout << vp[i].first <<     << vp[i].second <<   n ;     }   }   