wow that's good

Obviously, given that you have max, you can implement a prime number sieve if you want. There are a zillion kata on here that ask you to do just that.

not really... hard coding a prime list is not a great idea

One'd better blame the kata set up, which does not enforce the use of regex, than the warriors who solved it. Worst of all: this kata is available in Haskell, a language that has no regular expressions implemented natively :D

@zebulan who hurt you so badly?

I think he's still stuck.

You just deleted the equal signs. Did you really save that much space?
However, it's still not best practice for me. It's just a trick.

Argumentum ad populum. Nuff said.

Because in task was written to remove strings - not to keep only int.

@yoyotooie:

• You're right, it is easier than 6 kyu.
• Ranks cannot be changed (unless it's a site admin)
• Old kata => Overranked -- when they were created, the rank scale was different.

I agree with you. I cannot believe it. Way easier than some of the 7kyu kata i solved in the last couple of days.