Process starts with a general phone screen with a recruiter checking for general interest and some technical background. Next is a technical phone screen using codepad. The questions aren't generally hard; you just need to be prepared if you haven't interviewed in some time. As a note, definitely take notes when they start to describe the problem. Unlike any other technical screening I've had, they just told me the question and corner cases, etc. over the phone, and dumped a bunch of "self explanatory" test code into the codepad document. It's a lot to digest while someone is expecting you to think out loud on the other side of the line. Kinda awkward, tbh.

Thrifty algorithm.