Java Program to Compute Sum of Digit using Recursion of a given Number

Sum of Digit of a given number is addition of all its individual digits of that number.

Eg :sum of Digit of 12345 = 5+4+3+2+1 = 15

The following code calculates Sum of all its Digits of a given number using recursion.

```package com.javaonline;

import javax.swing.JOptionPane;

public class SumofDigit
{

public static void main(String[] args)
{
System.out.println("Enter the Number");

String input = JOptionPane.showInputDialog("Enter any column number: ");  // Getting Input

int sum = sod(Integer.parseInt(input));  // calling sum of digit function

System.out.println("Sum of the Digit of "+input+ " is " + sum);
System.exit(0);

}

// Computes a Sum of Digit of a number by recursion.

public static int sod(int n)
{

if(n < 10) return n;
return n%10 + sod(n/10);

}

}```

Compiling and Running the Program will give the below output:

Enter the Number
12345
Sum of the Digit of 12345 is 15

Enter the Number
97654
Sum of the Digit of 97654 is 31