import java.util.*;
import java.io.*;


public class B{
	static long gcd(long a, long b)
	{
		if(a == 0)return b;
		return gcd(b%a,a);
	}
	public static void main(String[] args)
	{
		FastScanner fs = new FastScanner();
		PrintWriter out = new PrintWriter(System.out);
		int t = fs.nextInt();
		for(int tt=0;tt<t;tt++)
		{
			int n = fs.nextInt();
			long[] arr = new long[n];
			long sum = 0;
			for(int i=0;i<n;i++)
			{
				long a = fs.nextLong();
				sum += a;
			}
			long extra = sum%n;
			
			long ans = 0;
//			out.println(extra);
			for(int i=1;i<=extra;i++)
			{
				ans += (n-i-(extra-i));
			}
			out.println(ans);
			
		}
		out.close();
	}
	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());
		}
	}
	public static int[] sort(int[] arr)
	{
		List<Integer> temp = new ArrayList();
		for(int i:arr)temp.add(i);
		Collections.sort(temp);
		int start = 0;
		for(int i:temp)arr[start++]=i;
		return arr;
	}
	public static String rev(String str)
	{
		char[] arr = str.toCharArray();
		char[] ret = new char[arr.length];
		int start = arr.length-1;
		for(char i:arr)ret[start--] = i;
		String ret1 = "";
		for(char ch:ret)ret1+=ch;
		return ret1;
//		return ret;
	}
}