using System;

public class Program

{

    public static void Main()

    {

        int a = 1;

        if(a == 1)

        {

            object test = null;

            while(a == 1)

            {

                a++;

                test = "12345";

                //test is defined

            } 

            var test2 = test;

            //test is undefined

            Console.WriteLine(test2);

        }

    }

}