You should work in teams, with one computer, for three hours starting at 10:00 pm. This is a completely honor-system based.
The online submit program linked here and to the main page should be working. If you get an incorrect judgment, but the output looks like just whitespace differences, that will be judged correct in the final post-judging phase (except for runtime exceeded, see below).
***Programs read from standard input***
If you run out of time (you'll get 30 seconds to run) you'll get incorrect output rather than runtime exceeded. If the program compiles, and the web page hangs for a while, your program is running, just wait. If it runs out of time you'll get back a diff of blanks and an "incorrect". You don't need more than 30 seconds for any problem.
***Programs read from standard input***
I'll monitor things for an hour or two, but I probably won't be able to fix broken stuff, though I'll try. You have the rest of the week to continue working with these problems.