Individual homeworks will be analysis and easier algorithm questions. For individual homework, you should solve and write the problems up yourself. Discussing basic techniques with classmates is OK, but there is a fine line between "discussing" (which is OK) and "getting the answer" (which is cheating). To ensure you don't cross the line, never make written notes while discussing individual homeworks. If you need to draw a picture or write something down, throw the paper away immediately.
Group homework will tend to involve finding efficient algorithms, and some may be hard. You should think about all problems, but only hand in ones that you are confident of your solutions. For group homework, you are encouraged to work in a group of up to three people, and write up a single solution. Each member of a group is responsible for understanding the solution (I may ask any one of you explain it to me.) You should not look for answers to homework problems in other books or papers. However, since you may be using other texts as a study tool, you may accidentally find a solution to a homework problems. In this case, write up your solution without consulting the text, and also give an acknowledgement of the text. On the group homeworks, your goal is to collect some "Very Good"'s and "Excellent"'s on some of the problems, and avoid "Incoherent"'s or "Wrong"'s. "Excellent" often means that I learned something new by reading your answer. "Very Good" means that it's clear that you have dug into the problem more than superficially.
Remember the following guidelines: