Write a program in java to accept a number and display the sum of its digits.

In mathematics, the digit sum of a given integer is the sum of all its digits (e.g. the digit sum of 84001 is calculated as 8+4+0+0+1 = 13).

import java.util.*;
class sum_of_digit
{
    public static void main(String args[])
    {
        Scanner sc=new Scanner(System.in);
        System.out.println("Enter the no.");
        int a,r=0,s=0;
        a=sc.nextInt();
        while(a>0)
        {
            r=a%10;
            s=s+r;
            a=a/10;
        }
        System.out.println("The sum of digit is="+s);
    }
}

Output: 
Enter the no:
213
The sum of digits is 6