Post Your Coding Chellange Here

Question

You can post your interesting coding challenge here.
No Homework or "I've got a problem with this" type, rather a cleverly formulated challenge requiring coding to solve. Look at some examples in the thread.
Use your feed to create the challenge and copy the link here.

Do not spam this with anything else, just the link to your post with a description.

Do all the answering in the linked post itself and not here.

Remember to select the little star on the bottom left of this for updates.

Answer 1

use the feed for this!