Write a program to find sum of right diagonals of a matrix

Write a program to find sum of right diagonals of a matrix.
#include<stdio.h>
int main()
{
  int m, n, row, col, a[10][10], Sum = 0;
 
  printf("Please Enter Number of rows and columns  :  ");
  scanf("%d %d", &m, &n);

  printf("\nPlease Enter the Matrix Elements\n");
  for(row = 0; row < m; row++)
   {
     for(col = 0; col < n; col++)
     {
        scanf("%d", &a[row][col]);
     }
   }
     
  for(row = 0; row < m; row++)
   {
     Sum = Sum + a[row][row];
   }
  printf("\nThe Sum of right diagonal elements of a Matrix =  %d", Sum);

  return 0;
}