Smith number

 A  Smith number is a composite number, the sum of whose digits is the sum of the digits of its prime factors obtained as a result of prime factorization (excluding 1). The first few such numbers are 4, 22, 27, 58, 85, 94, 121 ………………..

Examples:

1.  666

Prime factors are 2, 3, 3, and 37
Sum of the digits are (6+6+6) = 18
Sum of the digits of the factors (2+3+3+(3+7)) = 18

2.   4937775

Prime factors are 3, 5, 5, 65837
Sum of the digits are (4+9+3+7+7+7+5) = 42
Sum of the digits of the factors (3+5+5+(6+5+8+3+7)) = 42

Write a program to input a number (<1000) and display whether the number is a Smith number or not.

Input specification:The first line contains the value for N

Output specification:

print “ n is a Smith number“ or “ n is not a Smith number” or “n is an Invalid input”

Sample Input 1:

666

Sample Output 1:

666 is a Smith number

Sample Input 2:

102

Sample Output 2:

102 is not a Smith number

Sample Input 3:

1024

Sample Output 3:

1024 is an Invalid input

Source Code:-

import java.util.*;

class Test{

    public static void main(String []args){

        Scanner s=new Scanner(System.in);

        int n=s.nextInt();

        int i=2,m=n;

        int sum=0;

        int sumOfDig=sumOfDigit(n);

        if(n<1000){

            while(n>1){

                if(n%i==0){

                    sum=sum+sumOfDigit(i);

                    n=n/i;

                }

                else{

                    i++;

                }

            }

            if(sumOfDig==sum){

                System.out.println(m+" is a Smith number");

            }

            else{

                System.out.println(m+" is not a Smith number");

            }

        }

        else{

            System.out.println(n+" is an Invalid input");

        }

    }

    private static int sumOfDigit(int num){

        int sum=0;

        while(num>0){

            sum=sum+num%10;

            num/=10;

        }

        return sum;

    }

}