Summing the Major Diagonal of a Matrix in Java

Problem:

Write a method that sums all the integers in the major diagonal in an matrix of integers using the following header:

public static int sumMajorDiagonal(int[][] m)

Write a test program that reads a 4-by-4 matrix and displays the sum of all its elements on the major diagonal.

Output:

Fill in this 4x4 matrix
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16
Diagonal sum is 34

Solution:

import java.util.Scanner;

public class twoDimentionalArrays
{
  public static int sumMajorDiagonal(int[][] m)
  {
    int sum =0;
    for(int i =0;i<m.length;i++)
      sum += m[i][i];
    return sum;
  }
  
  public static void main (String[] args)
  {
    Scanner scan = new Scanner (System.in);
    System.out.println("Fill in this 4x4 matix");
    int[][] nums = new int[4][4];
    for (int i =0;i<nums.length;i++)
    {
      for (int j =0;j<nums[i].length;j++)
      {
        nums[i][j] = scan.nextInt();
      }
    }
    System.out.println("Diagonal sum is " + sumMajorDiagonal(nums));
  }
}