#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for (int i = 0; i < (n); i++)
#define FOR(i,a,b) for (int i = a; i <= b; i++)
#define FORD(i,a,b) for (int i = a; i >= b; i--)
#define MOD 1000000007

///// DEBUG TEMPLATE /////
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
///// DEBUG TEMPLATE /////

int n;
long long a[202020];

int main() {
	int nTest;
	cin >> nTest;
	while (nTest--) {
		cin >> n;
		FOR(i, 1, n) cin >> a[i];
		long long sum = 0;
		FOR(i, 1, n) sum += a[i];
		long long ave = sum / n;
		long long cnt_ave = n - sum % n;
		debug(ave);
		debug(cnt_ave);

			long long cnt_ave_1 = n - cnt_ave;
			cout << cnt_ave_1 * cnt_ave << endl;
	}
}
