Matrix Diagonals

For a square grid of numbers, the main diagonal runs from the top-left to the bottom-right and the anti-diagonal from the top-right to the bottom-left. Print the sum of each.

Input:

• Line 1: n, the size of the grid.
• Then n lines of n integers each.

Output: main anti, separated by a space. If n is odd, the centre cell belongs to both diagonals.

1 <= n <= 100, values between -1000 and 1000.