ISC COMPUTER SCIENCE PRACTICAL SOLVED 2021 QUESTION 1: FASCINATING NUMBERS

 QUESTION 1:

A Fascinating number is one which when multiplied by 2 and 3 and then, after the results are concatenated with the original number, the new number contains all the digits from 1 to 9 exactly once. There can be any number of zeros and are to be ignored.

Example: 273

                273 x 1 = 273

                273 x 2 = 546

                273 x 3 = 819

Concatenating the results we get, 273546819 which contains all digits from 1 to 9 exactly once.

Thus, 273 is a Fascinating number.

Accept two positive integers m and n, where m must be less than n and the values of both ‘m’ and ‘n’ must be greater than 99 and less than 10000 as user input. Display all Fascinating numbers that are in the range between m and n (both inclusive) and output them along with the frequency , in the format given below:

 

Test your program with the following data and some random data:

Example 1

INPUT                   m = 100

                                 n = 500

OUTPUT: THE FASCINATING NUMBERS ARE:

                192  219  273  327

                FREQUECNY OF FASCINATING NUMBERES IS: 4

Example 2

INPUT                   m = 900

                                 n = 5000

OUTPUT: THE FASCINATING NUMBERS ARE:

                1902  1920  2019  2190  2703  2730  3027  3270

                FREQUECNY OF FASCINATING NUMBERES IS: 8

Example 3

INPUT                   m = 400

                                 n = 900

OUTPUT: THE FASCINATING NUMBERS ARE:

                NIL

                FREQUECNY OF FASCINATING NUMBERES IS: 0

 

 import java.util.*;

public class ISC2021QUESTION1 {

       public static void main(String[] args) {

       int m,n;

       Scanner in = new Scanner(System.in);

       do {

        System.out.println("Enter the lower bound(m):");

        m = in.nextInt();

        System.out.println("Enter the upper bound(n):");

        n = in.nextInt();

       }while (m < 99 || n > 10000 || m < n); // conditions check

       Fascinating obj = new Fascinating(m,n);

       obj.generateFascinatingNumbers();

       in.close();

       }

}

class Fascinating {

    public void generateFascinatingNumbers() {

        System.out.println("THE FSCINATING NUMBERS ARE:");

        for (int i=m;i<=n;i++){

            if(isFascinating(i)==true) {

                System.out.println(" "+i+" ");

                frequency++;

            }

        }

        if(frequency==0) {

            System.out.println("NIL:");

            System.out.println("FREQUNCY OF THE FASCINATING NUMBERS IS:"+frequency);

        }

        else

            System.out.println("FREQUNCY OF THE FASCINATING NUMBERS IS:"+frequency);

    }

    private boolean isFascinating(int numb){

        int digitFrequency=0; // local variable

        String temp = "";

        // concatenating the numbers as stated

        temp = Integer.toString(numb)+Integer.toString(numb*2)+Integer.toString(numb*3);

        // checking that the frequecny of each digit is 1 or not

        for(int j=0; j < 9; j++){ // running through digit 1 to 9

            digitFrequency = 0;

            flag = true;

            for(int i=0;i<temp.length();i++){

                if(check.charAt(j)==temp.charAt(i)){

                    digitFrequency++;

                }

            }

            if(digitFrequency != 1) 

                flag = false;

            if(flag==false) 

                break;

        }

        return (flag == false? false : true);

    }

    Fascinating(int m, int n)    {

        this.n = n;

        this.m = m;

        frequency = 0;

    }

    private static String check = "123456789";

    private int n;

    private int m;

    private int frequency;

    private boolean flag;

}