Regular Expression

Just finish the exercise with http://regexone.com/

Great class at https://www.youtube.com/watch?v=EkluES9Rvak
and https://teamtreehouse.com/library/regular-expressions-in-java

Here is the cheatsheet to share,
https://docs.google.com/document/d/1mP9jo4cNCw3zx1D_IiA5ClVxM_mWe1Ss8woLqjB8ykg/edit?usp=sharing