Errors in the book

Exercise 10 and exercises 13, their code sample is switched. The code example of ex 10 is on 13 and vice versa.

Yes, do you have a paper copy of the book? That was an early mis-print.

I was reading from kindle cloud reader.

That’s not good. That should have been fixed long ago. Can you take a photo or screenshot of it and post it here or email it to help@learncodethehardway.org so I can tell the publisher.