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CIS 121: Spring 2019
Rajiv Gandhi
Teaching Assistants:
Course staff
Discussion Forum:
Tuesdays and Thursdays at 9:00am & 10:30am in Towne 100
Professor Office Hours:
Tuesday 12-1pm in Levine 512 & Friday 10-11am in Levine 307 or 4-5pm in Levine 512 (alternating, see calendar)
CIS 120 and CIS 160
Introduction to Algorithms, 3rd edition by Cormen, Leiserson, Rivest, and Stein. The lectures and the reading will draw from the textbook. It is strongly recommended that you buy this textbook or obtain a PDF copy.


The grading for the course will consist of:

  • 30% for homework assignments
  • 20% for each of two midterm exams
  • 25% for the final
  • 5% for recitation attendance and feedback/surveys. Recitation attendance is mandatory.
Late submission policy:

The following applies to all homeworks, both written and programming, unless otherwise specified. Each student can submit two assignments late. ‘Late’ means you may submit between 1 second and 48 hours after the homework deadline. These allowances are to accommodate things like mild sickness, interviews, computer crashes (see below), procrastination, etc. No additional late days will be granted for any of the above reasons. If you are out of late days, then your homework will receive a score of 0. Late homeworks can be turned in via Gradescope.

A word of advice:

We highly recommend using Overleaf for typing up written homeworks. This way if your computer crashes, you won’t lose all your hard work. For programming homeworks, we recommend backing up your computer regularly (Google, Microsoft OneDrive, etc. provide tools for automatically backing up your computer at scheduled intervals, or you can do this manually). You can also use GitHub, though make sure you only use private repos.

Collaboration policy for written homeworks:

You are allowed to discuss ideas for solving homework problems in groups of three, documenting who you discussed with at the top of your assignment. You are not allowed to write up the solutions together.

  • It is fine to discuss the topics covered in the homeworks, to discuss approaches to problems, and to sketch out general solutions. However, you MUST write up the homework answers and solutions individually. You are not permitted to share specific solutions, mathematical results, etc.
  • Our suggestion is to discuss the problems together, but if you made any notes or worked out something on a white board with another person while you were discussing the homework, then erase or destroy those notes as soon as the discussion is over. You shouldn’t use those notes while writing up your answer, however tempted you may be to do so. This will force you to write up the solutions yourself and to make sure that you genuinely and fully understand them.

Any violation of the collaboration policy will be dealt with severely.

Collaboration policy for programming homeworks:

You are allowed to discuss low-level issues like the meaning of Java constructs, or how to use the computing environment. You are allowed to discuss high-level questions such as what the instructor/lab TA said, the content of the textbook or other general resources. You are not allowed to…

  • Discuss issues directly pertaining to the homework questions or their solutions.
  • See another student’s homework solutions.
  • Show your solutions to another student.
    • This includes asking a classmate to debug your code and agreeing to debug a classmate’s code. If you do this in view of a TA, know that the TAs are required to report your names to the instructor.
  • Share any code except the code that is being made available by us on the course website to be used specifically with your solutions
    • Occasionally, a small snippet of code from the textbook may help your work. You can use such a snippet with attribution, i.e., provided you add a comment in which you make clear you copied it from the textbook.
    • You may NOT use snippets of code from the Internet (e.g., and similar).
    • You may NOT share test cases.
  • Post your code where it may be accessible to others. This is largely a clarification of the previous rule. This means that you may NOT seek help from online forums, like StackOverflow or similar. You may NOT push your code to a public repository like GitHub (private repositories, however, are permitted. Note that if you use a private repo, you must keep it private, even after the course ends). When in doubt, ask on Piazza.
  • Share the material that we post for this course with anybody who is not a registered student in this course or a staff member.
    • If you find any such material already posted somewhere else you must inform the course staff immediately. Use your common sense and ask any member of the staff if you are not sure about a resource you are considering.
    • You may NOT share course materials without the prior approval of the course staff. You may NOT post course materials on sites such as CourseHero. This infringes upon the copyright of materials authored by the course staff.

Any violation of the collaboration policy will be dealt with severely.

Regrade policy for written homeworks and exams:

Each written assignment and each midterm exam will have a regrade request deadline that will be posted typically one week after the assignment or exam has been returned with your score. Beyond that deadline, regrades can only be given by permission of the instructor. Regrade requests are meant for cases such as arithmetic mistakes in tabulating a final score, or for a grader not seeing that you continued your solution on the back of the page (as an example). In the interest of transparency, the course staff makes its best effort to indicate exactly where points are docked with the associated reasons. For the written assignments and for the midterms, solutions will be provided in class. Please consult these carefully before requesting a regrade. Please submit a regrade request via Gradescope by the regrade deadline.

Please note that we regrade the entire submission, so it’s possible for your score to go both up and down.

Regrade policy for programming homeworks:

We allow you to indicate small errors (defined below) that you have made, which, when fixed, will allow your programs to pass autograder tests. You will need to fill out a regrade request on Gradescope by the regrade deadline, which is usually one week after you receive your scores. In the form, you must identify exactly the error in your code and include a precise description of the fix that needs to be made (e.g. line numbers). A small error is a problem whose fix should generally require changing only 1 to 2 lines of code. Your new score will be the maximum of your original score and 80% of your regraded score. Examples of small errors:

  • Use of == instead of .equals
  • Modification of a method header, causing compilation failure
  • Lack or addition of ! operators
  • Forgetting to cast an int as a double
  • Forgetting to submit all required files

We reserve the right not to regrade fixes deemed too large.