using System;

public class Program

{

    static int doubleVar(int i)

    {

        i = i*2;

        return i;

    }

    static int doubleVarRef(ref int i)

    {

        i=i*2;

        return 5;

    }

    public static void Main()

    {

        // first let's call the function using the value

        int j=1;

        j = doubleVar(j);

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

        // now, let's call the function using the reference

        int x = doubleVarRef(ref j);

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

    }

}