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

public class B {
    public static void main(String[] args) throws IOException {
        try {
            // Unbuffered for interactive problem
            FastReader fs = new FastReader(new BufferedInputStream(System.in));
            PrintWriter out = new PrintWriter(System.out);
            int t = fs.nextInt();
            for (int ti = 0; ti < t; ti++)
	            {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;
				for(int i=1;i<=extra;i++)
				{
					ans += (n-i-(extra-i));
				}
				out.println(ans);
            }
        } catch (Throwable t) {
            t.printStackTrace(System.out);
            System.exit(1);
        }
    }

    private static final void log(Object o) {
        System.err.println(o);
    }

    private static class FastReader implements Closeable {
        private static final byte B_SP = ' ';
        private static final byte B_CR = '\r';
        private static final byte B_LF = '\n';
        private static final byte B_0 = '0';
        private static final byte B_9 = '9';
        private static final byte B_DASH = '-';

        private final InputStream in;
        private byte prev;

        public FastReader(InputStream in) {
            this.in = in;
        }

        public byte read() throws IOException {
            return (prev = (byte) in.read());
        }

        public byte readNonWs() throws IOException {
            byte b;
            do {
                b = read();
            } while (b <= B_SP);
            return b;
        }

        public int nextInt() throws IOException {
            byte b = readNonWs();
            final boolean neg = (b == B_DASH);
            if (neg) {
                b = read();
            }
            int i = (b - B_0);
            b = read();
            while (b >= B_0 && b <= B_9) {
                i = i * 10 + (b - B_0);
                b = read();
            }
            return neg ? -i : i;
        }

        public long nextLong() throws IOException {
            byte b = readNonWs();
            final boolean neg = (b == B_DASH);
            if (neg) {
                b = read();
            }
            long i = (b - B_0);
            b = read();
            while (b >= B_0 && b <= B_9) {
                i = i * 10 + (b - B_0);
                b = read();
            }
            return neg ? -i : i;
        }

        public int readToken(byte[] tbuf) throws IOException {
            byte b = readNonWs();
            int i = 0;
            do {
                tbuf[i++] = b;
                b = read();
            } while (b >= B_SP);
            return i;
        }

        public int readLine(byte[] lbuf) throws IOException {
            byte b;
            if (prev == B_CR) {
                b = read();
                if (b == B_LF) {
                    b = read();
                }
            } else {
                b = read();
            }
            int i = 0;
            while (b >= B_SP) {
                lbuf[i++] = b;
                b = read();
            }
            return i;
        }

        @Override
        public void close() throws IOException {
            in.close();
        }
    }
}