import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.StringTokenizer;

public class Solution{
	static FastScanner fs=new FastScanner();
	static void output(){
		int n = fs.nextInt();
		long[] a = new long[n];
		long sum = 0;
		for(int i=0;i<n;i++){
			a[i] = fs.nextLong();
			sum += a[i];
		}
		long d = sum/n;
		long mod = sum%n;
		if(mod != 0)
			d++;
		long x = d*n-sum;

		System.out.println((n-x)*x);

	}
	public static void main(String[] args) {
		
		int T = 1;
	    T=fs.nextInt();
		for (int tt=0; tt<T; tt++) {
			output();
		}
	}

	static void sort(int[] a) {
		ArrayList<Integer> l=new ArrayList<>();
		for (int i:a) l.add(i);
		Collections.sort(l);
		for (int i=0; i<a.length; i++) a[i]=l.get(i);
	}
	
	static class FastScanner {
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st=new StringTokenizer("");
		String next() {
			while (!st.hasMoreTokens())
				try {
					st=new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			return st.nextToken();
		}
		
		int nextInt() {
			return Integer.parseInt(next());
		}

		int[] readArray(int n) {
			int[] a=new int[n];
			for (int i=0; i<n; i++) a[i]=nextInt();
			return a;
		}

		long nextLong() {
			return Long.parseLong(next());
		}
	}
}
