Question

Can you answer this question in Java and explain your process?

Write a program that generates random numbers between 1 and 100 until the random number is a perfect number. You must compute all the divisors.

Answer 1

Ans :

Steps to solve the problem:

1. use while loop and give parameter as true untill random number is generted is a perfeect number
2. inside while loop generate random number at each iteration
3. create a function with name checkPerfect(int n) that will check that a number is perfect number or not. for checking that a number is prime or not simply iterate the loop from 1 to n-1 and check it is a divisor if it is then simply add it to the sum if sum is equal to the number than it is a perfect number and return true else return false.
4. if random number generated is perfect then simply break out from the while loop.

Java code :

/* importing random class to generate random number*/
import java.util.Random;
public class Perfect {


    //creating function to check random number is perfect or not
    public static boolean checkPerfect(int n)
    {
        //declaring sum variable
        int sum=0;


        //iterating loop till n-1 to check prime divisor
        for (int i=1;i<n-1;i++)
        {
            //if i is prime divisor the add it to the sum
            if (n % i==0)
            {
                sum = sum + i;
            }
        }
/* //checking that number is equal to the sum of all its divisor if yes return true
* else return false*/

        if (sum == n && n != 1)
            return true;

        return false;
    }

    public static void main(String[] args) {

        //creating object of random number class
        Random random=new Random();

        //executing loop till condtion is true
        while(true)
        {
            //generating random number
            int i=random.nextInt(100);

            //function call for checkPerfect function
            if(checkPerfect(i))
            {
                //if it perfect number simply break out from the loop
                System.out.println("Random number "+i +" is  a perfect number");
                break;
            }
            else

                System.out.println("Random number "+i +" is  not a perfect number");
        }




    }

}

output images :

→ If Random number 62 is not a perfect number Random number 43 is not a perfect number Random number 25 is not a perfect number Random number 15 is not a perfect number Random number 5 is not a perfect number Random number 1 is not a perfect number Random number 62 is not a perfect number Random number 1 is not a perfect number Random number 60 is not a perfect number Random number 67 is not a perfect number Random number 11 is not a perfect number Random number 45 is not a perfect number Random number 60 is not a perfect number Random number 63 is not a perfect number Random number 3 is not a perfect number Random number 85 is not a perfect number Random number 36 is not a perfect number Random number 99 is not a perfect number Random number 15 is not a perfect number Random number 91 is not a perfect number Random number 97 is not a perfect number Random number 7 is not a perfect number Random number 75 is not a perfect number Random number 27 is not a perfect number Random number 5 is not a perfect number Random number 26 is not a perfect number Random number 39 is not a perfect number Random number 28 is a perfect number Process finished with exit code 4: Run E 6: TODO Terminal All files are up-to-date (moments ago)

code image :

Activities IntelliJ IDEA Community Edition Thu 02:13: core-java (-/IdeaProjects/core-java] -.../src/Perfect.java File Edit View Navigate Code Analyze Refactor Build Run Tools VCS Window Help core-java src d Perfect u c Perfect.java * Perfect C Q I 1: Project * Ant /* importing random class to generate random number*/ import java.util. Random; public class Perfect { //creating function to check random number is perfect or not public static boolean checkPerfect(int n) //declaring sum variable int sum=0; //iterating loop till n-1 to check prime divisor for (int i=1;i<n-1;i++) //if i is prime divisor the add it to the sum if (n % i==0) sum = sum + i; : 7: Structure /* /checking that number is equal to the sum of all its divisor if yes return true ** else return false*/ if (sum == n && n != 1) return true; return false; * 2: Favorites Perfect > checkPerfect() 4: Run E 6: TODO Terminal O All files are up-to-date (3 minutes ago) Event Log 9:5 LF UTF-8 4 spaces

Activities IntelliJ IDEA Community Edition Thu 02:13: core-java (-/IdeaProjects/core-java] -.../src/Perfect.java File Edit View Navigate Code Analyze Refactor Build Run Tools VCS Window Help core-java src Perfect ud Perfect.java Perfect C o Q 1: Project * Ant public static void main(String[] args) { //creating object of random number class Random random=new Random(); //executing loop till condtion is true while(true) //generating random number int i=random.nextInt( bound: 100); //function call for checkPerfect function if (checkPerfect(i)) //if it perfect number simply break out from the Loop System.out.println("Random number "+i +" is a perfect number"); break; else System.out.println("Random number "+i +" is not a perfect number"); : 7: Structure * 2: Favorites Perfect > checkPerfect() 4: Run = 6: TODO 2 Terminal O All files are up-to-date (3 minutes ago) Event Log 9:5 LF UTF-8 4 spaces