Java: Compute the sum of the digits in an integer

Last update on March 11 2025 11:09:09 (UTC/GMT +8 hours)

Sum of Digits in Integer

Write a Java method to compute the sum of digits in an integer.

Test Data:
Input an integer: 25

Pictorial Presentation:

Sample Solution:

Java Code:

import java.util.Scanner;
public class Exercise6 {

  public static void main(String[] args)
    {
      Scanner in = new Scanner(System.in);
      System.out.print("Input an integer: ");
      int digits = in.nextInt();
	  System.out.println("The sum is " + sumDigits(digits));
    }

 public static int sumDigits(long n) {
		int result = 0;
		
		while(n > 0) {
			result += n % 10;
			n /= 10;
		}
		
		return result;
	}
	
 }

Sample Output:

Input an integer: 25                                                                                          
The sum is 7

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to compute the product of the digits of an integer using a loop.
• Write a Java program to calculate the digital root of an integer by recursively summing its digits.
• Write a Java program to sum only the even digits of a given integer.
• Write a Java program to sum the digits of an integer without converting it to a string.

Java Code Editor:

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