primesGoldbach

import java.util.*;
public class FunPrimes
{
    
    public FunPrimes()
    {
        LinkedList list = new LinkedList();
        
        Scanner sc = new Scanner(System.in);
        boolean playing = true;
        System.out.println("Welcome to the prime number checker!");
        while(playing){
            System.out.print("Enter a number to check if it's prime:");
            int num = sc.nextInt();
            if(checkPrime(num)){
                System.out.println(num + " is a prime.");
                list.insert(list, num);
            }else{
                System.out.println(num + " is not a prime.");
            }
            goldbach(num);
            if(list.getSize(list)!=0){
                System.out.print("your prime list: ");
                list.printList(list);
                System.out.println();
            }
            System.out.println("Keep Going? ('Y' or 'N')");
            String cont = sc.next();
            if(cont.equals("N"))
                playing = false;
        }
    }

    public boolean checkPrime(int y)
    {
        boolean prime = true;
        if(y==0||y==1){
            prime = false;
        }else{
            for(int i = 2; i < y; i++){
                if(y%i==0)
                    prime = false;
            }
        }
        
        return prime;
    }
    
    public void goldbach(int y){
        
        //int[] primes = new int[2];
        //primes[0] = 0;
        //primes[1] = 0;
                
        if(y > 0){
            if(y%2==0 & y>2){
                for(int i = 3; i <= y/2; i++){
                    if(checkPrime(i)&&checkPrime(y-i)){
                        System.out.println(y + " is the sum of the prime numbers " + i + " and " + (y-i));
                    }
                }
            }else{
                System.out.println("Parameter is an odd number.");
            }   
        }
        
        //return primes;
    }
}