using System;

​

public class Program 

{

    // Global d

    static int d = 20;

    public static void Main()

    {

        // can't declare variable twice in the same scope

        int x = 20;

        // some code

        // int x = 30;

        // Local d

        int d = 10;

        Console.WriteLine("Local d : {0}",d);

        // refer to global variable (d) using scope qualifier

        Console.WriteLine("Global d : {0}", Program.d);

        // i is declared twice but in a different scope

        for (int i = 0; i < 10; i++)

        {

            Console.WriteLine("i first loop : {0}", i);

        } // first i goes out of scope here

        // We can declare a variable named i again, because

        // there's no other variable with that name in scope

        for (int i = 9; i >= 0; i-- )

        {

            Console.WriteLine("i second loop : {0}",i);

        } // second i goes out of scope here.

    } 

}