No, you don't have to sign up again. It was decided to extend the deadline from the end of 2015 to the end of 2016, so your grades received from last year continue forward to this year. However, for assignments that you have not yet completed, you will need to do the assignments for the 2016 class going forward. Some are the same, some have minor changes, and some have significant changes.
You will also want to use the cloud based IDE now, as it has been adopted as the standard development environment for the class. (Last year's license for the VMware env. will expire in a few days.) Instructions can be found in the week 1 / pset1 assignment.
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