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Reena had been given an array arr[] of positive integers of size N.Help her to find the value A.

A = arr[n]*arr[n] - arr[n-1]*arr[n-1] + arr[n-2]*arr[n-2] - ......... upto index 1

**Input: **

1. The first line of the input contains a single integer* * T denoting the number of test cases. The description of T test cases follows.

2. The first line of each test case contains a single integer N.

3. The second line contains N space-separated positive integers represents array arr.

**Output:** For each test case, print the value of A in a single line

**Constraints:**

1. 1 <= T <= 10

2. 1 <= N <= 100000

3. 1 <= arr[i] <= 100

**Example:
Input:**

2

3

1 2 3

4

4 8 1 2

**Output:**

6

51

**Explanation:**

Test case 1 : 3*3 - 2*2 + 1*1 = 6

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Reverse squared sum

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