That's wrong, although 'flipped' is the preferred one, 'inverted' definitely makes no sense.

Thanks! I fixed the namespace.
You also make a great point about using static.
I guess I was thinking about it as a first step to making a class that would not be empty.
But as far as coding THIS kata, I completely agree.
I'll have to think about it some more but I'll either update the description to indicate that more clearly or I'll change it to work as static.

Initial code has the wrong namespace and class name.

Moreover, shouldn't GetCell be a static method? I don't see why we have to instantiate an empty, useless class just to use a method.

lol, I just saw this as a smile comment at first. Now I relize it is answer to my question before I even ask. Wish the tests had caught it or that I had relized to add it as a test case.

We made same solution. My initializer just on one line :)
I like this way because:
Just uses Linq so do not have to bring along 2 libraries.
Set of valid smileys is small and not likly to change once specified for the project; so why not just make array. Also really simple to add/remove valid smileys if it did.
And very simple for pretty much anyone to read the code.

I'm curious why you recomend RegEx over this?

Sure it's spelled out in the description to round down, but it still also bugs me that we don't cover full cost.

Was thinking when I read that the photocopier reversed it, that it would be somthing more like mirror symmetry (110|011).
Maybe say it inverted the digits instead of reversed?
Thanks for kata!