I would give myself about ~30 min (or less, sometimes more) for each question. Most interview questions are from the excellent cracking the coding interview book. I chose Python as a programming language as it writes almost like pseudo code.
It was a good review overall and a pretty fun exercise to get things well in place :)
The extra directory holds some questions not found in the book but asked during an actual interview.
Note: it is very likely that some answers do have bugs. The idea was to write the most optimal solution but in the shortest amount of time possible!