Number Operations (Sum, Count, Reverse) Using Loop in Java

1. Sum of Digits

java

public class Main {
    public static void main(String[] args) {
        int num = 1234, sum = 0;

        while (num > 0) {
            sum += num % 10;
            num =num/ 10;
        }

        System.out.println("Sum = " + sum);
    }
}

output

2. Count of Digits

java

public class Main {
    public static void main(String[] args) {
        int num = 1234, count = 0;

        while (num > 0) {
            num =num/ 10;
            count++;
        }

        System.out.println("Count = " + count);
    }
}

output

3. Reverse a Number

 public class Main {
    public static void main(String[] args) {
        int num = 1234, rev = 0;

        while (num > 0) {
            rev = rev * 10 + num % 10;
            num =num/ 10;
        }

        System.out.println("Reverse = " + rev);
    }
}

output