using System;

public class Program

{

    public static void Main()

    {

    try

    {

        Method1();

    }

    catch(Exception ex)

    {

        Console.WriteLine(ex);

    }                      

}

​

static void Method1()

{

    try

    {

        Method2();

    }

    catch(Exception ex)

    {

        throw ex;

    } 

}

​

static void Method2()

{

    string str = null;

    try

    {

        Console.WriteLine(str[0]);

    }

    catch(Exception ex)

    {

        throw;

    } 

}

}