// Wikipedia for Harshad Number : https://en.wikipedia.org/wiki/Harshad_number

package Maths;

import java.util.Scanner;

public class HarshadNumber
{
 public static void main(String[] args) {
 Scanner sc = new Scanner(System.in);
 System.out.print("Enter a number : ");
 long a = sc.nextLong();
 
 checkHarshadNumber(a);
 }

 /**
 * A function to check if a number is Harshad number or not
 *
 * @param a The number which should be checked 
 */
 public static void checkHarshadNumber (long a) {
 
 long b = a;
 int sum = 0;
 
 // this is just for showing the explanation else it's of no use you can ommit it
 int[] each = new int[Long.toString(a).length()];
 
 int c = 0;
 
 while (b > 0) {
 sum += b % 10;
 each[c] = (int)(b%10);
 b /= 10;
 c++;
 }
 
 if (a % sum == 0){
 System.out.println(a + " is a Harshad Number");
 
 // For you better explanation how is that a Harshad Number
 System.out.println("\nExplaination :");
 
 for (int i = each.length-1; i >=0; i--){
 System.out.print(each[i] + " ");
 if (i != 0) {
 System.out.print("+ ");
 }
 }
 
 System.out.println("= " + sum);
 System.out.println(sum + " ×ばつ " + (a / sum) + " = " + a);
 }
 
 else {
 System.out.println(a + " is not a Harshad Number");
 }
 }
}