Create Sum of diagonals

[Ctrl-apk]

Problem

Adding the diagonal elements(Both primary and secondary)

Solution

1. A simple matrix will be taken as input from the user

2. Method calculateSum takes a simple 2D array as input in which
   a)it calculates sum of primary diagonal and secondary diagonal.
   b)If matrix is of odd dimensions,the center element is subtracted from the sum because it gets counted twice.

3. Output will be sum of both diagonals printed.

[Ctrl-apk]

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