## Diagonal Difference

Given a square matrix of size , calculate the absolute difference between the sums of its diagonals.

**Input Format**

The first line contains a single integer, . The next lines denote the matrix's rows, with each line containing space-separated integers describing the columns.

**Constraints**

**Output Format**

Print the absolute difference between the two sums of the matrix's diagonals as a single integer.

**Sample Input**

```
3
11 2 4
4 5 6
10 8 -12
```

**Sample Output**

```
15
```

**Explanation**

The primary diagonal is:

```
11
5
-12
```

Sum across the primary diagonal: 11 + 5 - 12 = 4

The secondary diagonal is:

```
4
5
10
```

Sum across the secondary diagonal: 4 + 5 + 10 = 19

Difference: |4 - 19| = 15

**Note:** |x| is absolute value function