58.23

Given a matrix of **n X n**. The task is to calculate the absolute difference between the sums of its diagonal.

```
Input : A[][] = 11 2 4
4 5 6
10 8 -12
Output : 15
Sum of primary diagonal = 11 + 5 + (-12) = 4.
Sum of primary diagonal = 4 + 5 + 10 = 19.
Difference = |19 - 4| = 15.
```

**Input:**

The first line of input consists of T, denoting the Test Cases. Then T test cases follow. The first line of every test case consists of N, denoting the size of matrix N X N. The second line of every test case consists of N*N spaced integers Ai.

**Output:**

For each test case in a single line print an integer denoting the difference between the sum of its diagonals.

**Constraints:**

1<=T<=100

1<=N<=50

1<=Ai<=100

**Example:
Input:**

2

3

11 2 4 4 5 6 10 8 -12

4

1 2 3 4 5 9 7 8 6 10 11 12 13 14 15 16

15

3