func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int t = 1;     cin >> t;     while (t--) {       int n;       cin >> n;       if (n == 2) {         cout <<  2 n1 2 n ;         continue;       }       vector<pair<int, int>> ans;       int cur = n;       for (int i = n - 1; i >= 1; --i) {         ans.push_back(make_pair(i, cur));         cur = (cur + i + 1) / 2;       }       cout << cur <<   n ;       for (auto i : ans) cout << i.first <<     << i.second <<   n ;     }     return 0;   }   