Example: Sum of Digits using While Loop in Java

// Sum of Digits using While Loop
import java.util.Scanner;

// Main class containing the entry point of the program
public class Main {
    public static void main(String[] args) {
        // Step 1: Create a Scanner object to read input from the user
        Scanner scanner = new Scanner(System.in);

        // Step 2: Prompt the user to enter a number
        System.out.print("Enter a number: ");
        int number = scanner.nextInt(); // Read the integer input

        // Step 3: Initialize a variable to store the sum of digits
        int sumOfDigits = 0;

        // Step 4: Use a while loop to extract and sum digits
        // The loop continues as long as the number is greater than 0
        while (number > 0) {
            // Step 4a: Get the last digit using the modulo operator (%)
            int digit = number % 10;

            // Step 4b: Add the extracted digit to the sum
            sumOfDigits += digit;

            // Step 4c: Remove the last digit from the number using integer division (/)
            number /= 10; // Equivalent to number = number / 10;
        }

        // Step 5: Print the final sum of digits
        System.out.println("Sum of digits: " + sumOfDigits);

        // Step 6: Close the scanner to prevent resource leaks
        scanner.close();
    }
}