Need to explain all steps

Given a square matrix M of odd dimensions (3 by 3, 5 by 5 or larger): Write a MATLAB function [centercross] = centercross(M) to make zero the elements of the middle column, the middle row and the perimeter (first row, last row. first column, last column) of the matrix, as shown below. The rest of the entries in the matrix should remain unchanged. Vectorize your code as much as possible. Your code should work in general with any square matrix of odd dimensions. Example 1: 1-3 2 4 2 5 7 8 9 5 3 2 4 6 3 6 8 2 13 3 3 3 3 3 Becomes: 0 0 0 0 0 0 7 0 9 0 0 0 0 0 0 0 8 0 1 0 0 0 0 0 0 Example 2 1 -3 2 4 2 5 3 5 7 8 9 5 3 2 3 2 4 6 3 4 1 6 8 2 1 3 5 4 3 3 3 3 3 6 3 2 2 2 2 2 2 7 3 5 6 1 4 6 2 Becomes: 0 0 0 0 0 0 0 0 7 8 0 5 3 0 0 2 4 0 3 4 0 0 0 0 0 0 0 0 0 3 3 0 3 6 0 0 2 2 0 2 2 0 0 0 0 0 0 0 0 Discussion or calculations made