func_code_string: #include <bits/stdc++.h>   #define debug(a) cout << #a <<  :   << a <<   n    #define debugLine() cout <<  ============== n    #define tick() cout <<  Tick n ;   #define testCases() int t; cin >> t; while(t--)   #define all(a) a.begin(), a.end()   #define fillWith(a, b) memset(a, b, sizeof(a))   #define INF_32 1e9   #define INF_64 1e18   #define Mod 1000000007   #define PI 3.14159265358979323846   #define endl   n    #define goFast() ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)   typedef long long ll;   using namespace std;      int main()   {       goFast();       testCases()       {           ll n;           cin >> n;           ll arr[n + 3];           ll sum = 0;           for(int i = 0; i < n; i++)           {               cin >> arr[i];               sum += arr[i];           }           cout << (n - sum % n) * (sum % n) << endl;       }   }