codeforces.py

'''
While exploring the jungle, you have bumped into a rare orangutan with a bow tie! You shake hands with the orangutan and offer him some food and water. In return...

The orangutan has gifted you an array 𝑎
 of length 𝑛
. Using 𝑎
, you will construct two arrays 𝑏
 and 𝑐
, both containing 𝑛
 elements, in the following manner:

𝑏𝑖=min(𝑎1,𝑎2,…,𝑎𝑖)
 for each 1≤𝑖≤𝑛
.
𝑐𝑖=max(𝑎1,𝑎2,…,𝑎𝑖)
 for each 1≤𝑖≤𝑛
.
Define the score of 𝑎
 as ∑𝑛𝑖=1𝑐𝑖−𝑏𝑖
 (i.e. the sum of 𝑐𝑖−𝑏𝑖
 over all 1≤𝑖≤𝑛
). Before you calculate the score, you can shuffle the elements of 𝑎
 however you want.

Find the maximum score that you can get if you shuffle the elements of 𝑎
 optimally.

Input
The first line contains 𝑡
 (1≤𝑡≤100
) — the number of test cases.

The first line of each test case contains an integer 𝑛
 (1≤𝑛≤1000
) — the number of elements in 𝑎
.

The following line contains 𝑛
 integers 𝑎1,𝑎2,…,𝑎𝑛
 (1≤𝑎𝑖≤1000
) — the elements of the array 𝑎
.

It is guaranteed that the sum of 𝑛
 over all test cases does not exceed 1000
.

Output
For each test case, output the maximum score that you can get.

solution as follows
'''
test = int(input())
for _ in range(test):
    n = int(input())
    arr = list(map(int,input().split()))
    maxa = max(arr)
    mina = min(arr)
    diff=maxa-mina
    ans = int(diff*(n-1))
    print(ans)