Use of unassigned local variable?

[JungleHeart]

Greetings,

I am completely new to programming and also to C#. I'm working out of a book called "Beginning C# 6 Programming with Visual Studio 2015". There is an example that I'm having trouble de-bugging and I swear I have typed everything exactly as in the book! but perhaps I'm missing something... I keep getting the error : Use of unassigned local variable 'firstNumber'
here is the code:

{


            double firstNumber, secondNumber;
            string userName;
            Console.WriteLine("Enter your name:");
            userName = Console.ReadLine();
            Console.WriteLine($"Welcome {userName}!");
            Console.WriteLine("Now give me a number:");
            secondNumber = Convert.ToDouble(Console.ReadLine());
            Console.WriteLine($"The sum of {firstNumber} and {secondNumber} is " +
                $"{firstNumber + secondNumber}.");
            Console.WriteLine($"The result of subtracting {secondNumber} from " +
                $"{firstNumber} is {firstNumber - secondNumber}.");
            Console.WriteLine($"The result of dividing {firstNumber} by " +
                $"{secondNumber} is {firstNumber / secondNumber}.");
            Console.WriteLine($"The remainder after dividing {firstNumber} by " +
                $"{secondNumber} is {firstNumber % secondNumber}.");
            Console.ReadKey();


        }

Can someone help??? Thanks in advance!!!

 

[JohnH]

You use firstNumber without having assigned something to it beforehand. You can assign when declaring it:

double firstNumber = 0;

 

[JungleHeart]

thanks!

You use firstNumber without having assigned something to it beforehand. You can assign when declaring it:

double firstNumber = 0;

Excellent, Thanks!
I'll let the authors of the book know about the mistake...

 

[VitzzViperzz]

How are you finding the book so far?