Given a square matrix, calculate the absolute difference between the sums of its diagonals.
For example, the square matrix is shown below:
1 2 3
4 5 6
9 8 9
- The left-to-right diagonal = .
- The right-to-left diagonal = .
Their absolute difference is .
Function description
Complete the function with the following parameter:
- : a 2-D array of integers
Return
- : the absolute difference in sums along the diagonals
Input Format
The first line contains a single integer, , the number of rows and columns in the square matrix .
Each of the next lines describes a row, , and consists of space-separated integers .
Constraints
Sample Input
STDIN Function
----- --------
3 arr[][] sizes n = 3, m = 3
11 2 4 arr = [[11, 2, 4], [4, 5, 6], [10, 8, -12]]
4 5 6
10 8 -12
Sample Output
15
Explanation
The primary diagonal is:
11
5
-12
Sum across the primary diagonal: .
The secondary diagonal is:
4
5
10
Sum across the secondary diagonal:
Difference:
Note: |x| is the absolute value of x.