using System;

public class Program

{

    public static bool Primenum (int num)

    {

        int count1=0;

        for (int i=1; i<=num; i++)

        {

            if (num%i==0)

            {

                count1++;

            }

        }

        if (count1==2)

            {

                return true;

            }

            else 

            {

                return false;

            }

    }

    public static void Main(string[] args)

        {

            Console.WriteLine("enter the value of n:");

            int n = int.Parse(Console.ReadLine());

            for (int j=1; j<=n; j++)

            {

                bool pn1 = Primenum(j);

                bool pn2 = Primenum(j+2);

                if ((pn1=true)&&(pn2==false))

                {

                    Console.WriteLine(j+"+"+j+2);

                }

            }

        }

}