Define a class to accept a 3 digit number and check whether it is a duck number or not. Note: A number is a duck number if it has zero in it.

import java.util.Scanner;

public class KboatDuckNumber
{
    public static void main(String args[]) 
    {
        Scanner in = new Scanner(System.in);
        System.out.print("Enter a number: ");
        int num = in.nextInt();
        int n = num;
        int count = 0;
        
        while (n != 0)    {
            count++;
            n = n / 10;
        }
        
        if (count == 3)
        {
            n = num;
            boolean isDuck = false;
            while(n != 0) 
            {
                if(n % 10 == 0)  
                {  
                    isDuck = true;
                    break;
                }
                n = n / 10;  
            }
            
            if (isDuck) {
                System.out.println("Duck Number");
            }
            else {
                System.out.println("Not a Duck Number");
            }
        }
        else {
            System.out.println("Invalid");
        }
    }
}