Bloomberg Big Data Engineer interview questions

The first step was a task that was explained by the interviewer over the phone, and was to be completed at home within about 20 minutes and be sent by email for review (the task: remove duplicate consecutive spaces from a string, in-place). The second step was an on-site coding task that was scheduled to take up to 4 hours, but was described by the interviewer as doable in about two hours. I don't remember the specifics of the on-site task, but it had to do with building a very simple file system, where the interface was given.