Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

C# C# Basics (Retired) Perfect Final

Hung Cao
Hung Cao
503 Points

I'm stuck on this Final Challenge. Can someone helps me?

It keeps saying that there is a NullReferenceException error. But I do not know where to fix it

Program.cs
using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {


            int totalLoopTime = 0;

            while  (true)
            {
                Console.Write("Enter the number of times to print \"Yay!\": ");
                var reply = Console.ReadLine();

                if (reply.ToLower() == "quit")
                {        
                    break;               
                }

                try
                {
                    var time = int.Parse(reply);
                    totalLoopTime += time;

                    for (int i = 1; i <= totalLoopTime; i++)
                    {
                    Console.WriteLine(i + ". Yay!");
                    }
                    Console.WriteLine("You have total of " + totalLoopTime + " loops since the begginning");    


                }
                catch(FormatException)
                {
                    Console.WriteLine("That is not a valid input! Please provide a whole number!");
                    continue;
                }


            }
        }
    }
}

1 Answer

Steven Parker
Steven Parker
231,236 Points

:point_right: Your program deviates from the instructions.

This has been a topic of many previous questions, but I'll repost the info here:

People often over-think this one and get too creative, and their answer is rejected for a variety of reasons (some which don't seem to make any sense).

Here are the secret "rules" you must follow for success on this one:

  • Your program must ask for and accept input ONE TIME ONLY (no looping!)
  • If the input validates, your program will perform exactly as in Task 1
  • If the input does not validate, it will print the error message and exit
  • Validation must be done by exception catching. There are other perfectly good methods that can be used for validation, but they will not pass this challenge