Task3

package HomeWork_Programming;

import java.util.*;
import java.lang.Math;

public class Task3 {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);

        //Creating LinkedList
        LinkedList ll = new LinkedList();

        int n;
        do {                                      //Input only positive numbers
            n = Integer.parseInt(scan.nextLine());
            if (Math.sqrt(n) == Math.round(Math.sqrt(n))){       //Check if number is square root and add to list
                ll.add(n);
            }
        }
        while(n > 0);     //Exit is with negative value

        Collections.sort(ll,  Collections.reverseOrder());    //Sort the list in descending order
        for (int i = 0; i <ll.size(); i++) {          //Output results
            System.out.print(ll.get(i)+ " ");
        }

    }//end of main
}//end of class