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ISC 2021 Program: Fascinating Number

Write a Program in Java to input a number and check whether it is a Fascinating Number or not.
Fascinating Numbers: Some numbers of 3 digits or more exhibit a very interesting property. The property is such that, when the number is multiplied by 2 and 3, and both these products are concatenated with the original number, all digits from 1 to 9 are present exactly once, regardless of the number of zeroes.
Let's understand the concept of Fascinating Number through the following example:
Consider the number 192
192 x 1 = 192
192 x 2 = 384
192 x 3 = 576
Concatenating the results: 192 384 576
It could be observed that '192384576' consists of all digits from 1 to 9 exactly once. Hence, it could be concluded that 192 is a Fascinating Number. Some examples of fascinating Numbers are: 192, 219, 273, 327, 1902, 1920, 2019 etc.
/**
 * suppose 192
 * 192x1=192
 * 192x2=384
 * 192x3=576
 * 192384576
 * no single digit should repeat
*/

import java.util.Scanner;
class fascinating
{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter a number: ");
        int n = sc.nextInt();
        long m = Long.parseLong(String.valueOf(n)+String.valueOf(n*2)+String.valueOf(n*3));
        int arr[] = new int[10];
        while(m>0)
        {
            int r = (int)(m%10);
            arr[r]++;
            m=m/10;
        }
        boolean flag=false;
        for(int i=0;i<arr.length;i++)
        {
            if(arr[i]>=2)
                {
                    flag=true;
                    break;
                }
        }
        if(!flag)
            System.out.println(n+"is a fascinating number");
        else
            System.out.println(n+"is not a fascinating number");
    }
}

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