Working with 2D arrays is quite important. Here we will do swapping of column in a 2D array. You are given a matrix M or r rows and c columns. You need to swap the first column with the last column.

Example:

Input:
3 4
1 2 3 4
4 3 2 1
6 7 8 9

Output:
4 2 3 1
1 3 2 4
9 7 8 6

Your Task:
Since this is a function problem, you don't need to take any input. Just complete the provided function interchange(int, int , int ) that take matrix, rows and columns as parameters.

Constraints:
1 <= r,c <= 100