B'Given an array a of n elements, find the maximum value of the expression: |a_i - a_j| + |a_j - a_k| + |a_k - a_l| + |a_l - a_i| where i , j , k , and l are four distinct indices of the array a , with 1 <= i, j, k, l <= n . Here |x| denotes the absolute value of x . The first line contains one integer t ( 1 <= t <= 500 ) -- the number of test cases. The description of the test cases follows. The first line of each test case contains a single integer n ( 4 <= n <= 100 ) -- the length of the given array. The second line of each test case contains n integers a_1, a_2, ldots, a_n ( -10^6 <= a_i <= 10^6 ). For each test case, print a single integer -- the maximum value. In the first test case, for any selection of i , j , k , l , the answer will be 0 . For example, |a_1 - a_2| + |a_2 - a_3| + |a_3 - a_4| + |a_4 - a_1| = |1 - 1| + |1 - 1| + |1 - 1| + |1 - 1| = 0 + 0 + 0 + 0 = 0 . In the second test case, for i = 1 , j = 3 , k = 2 , and l = 5 , the answer will be 6 . |a_1 - a_3| + |a_3 - a_2| + |a_2 - a_5| + |a_5 - a_1| = |1 - 2| + |2 - 1| + |1 - 3| + |3 - 1| = 1 + 1 + 2 + 2 = 6 . '...