I've posted a few questions on it but there is a lack of feedback. So, my first submission for pset1 passed check50 but received 0.68 because I forgot to cite snippeted code in mario.c. When looking for some answers for questions I had on mario.c, I accidently clicked a solution website. I immediately backed out of the website without using any of the code. I cited all of my code in the comments of all of my programs and resubmitted all of my code.

Everything besides hello.c received a grade of 0. My total grade for this resubmission was 0.04. I tweaked my code, improved my citation, and submitted pset1 again. My new score was 0. I don't understand why, since my code passes check50 and style50, I'm receiving such low scores. Is there a problem with the grading system? Is it because I accidently clicked on a solution site, even if I didn't mean to and backed out immediately? I've emailed the staff and have posted other questions and have received no answers. Thanks in advance.

1 Answer 1


Remember: when you resubmit pset1, you must resubmit all sources according to instructions:

If you’d like to re-submit different (or modified) files, simply return to CS50 Submit and repeat these steps.

It is important that you submit the source codes with the exact names called for in the spec (hello.c, mario.c, water.c, greedy.c).

I can't speak for the staff, but the new Harvard session starts this Friday (or so), and the staff's focus is surely on that. (In other words, responses to edX inquiries may take longer than usual).

If am speculating that you found yourself at the "postemortems" when you say " I accidently clicked a solution website". There is a multiple step validation process, and if you never saw the solution, this is not likely a factor in your problem.

I suggest you slowly and methodically review these things.

  1. Run check50 again for each exercise and make sure you get "all green checks". If not, then you know you will have to find out what is wrong with your code, fix it, and resubmit.

  2. Navigate to the gradebook. Totally "open" Problem Set 1. Click all the ► on the left hand side. Problem Set 1, then Hello, then Water, etc. You should see a score at the right for each test in each exercise. If that does not match the result of check50 then maybe the version of the code that you submitted does not match the version on your IDE (the one check50 just evaluated).

  3. Verify the code on your ide matches the code you submitted. Navigate to the Submit page. Select Problem Set 1 from the list on the left. It will show you a history of each submission by date. If you click on the most recent date, it will open a new page with a list of your submitted codes on the right left. When you click on something in the list it will offer a download icon. You can download (or open in Notepad or similar) to your local pc. If the code in the gradebook is different from the code on your IDE, that could surely cause a difference in results. They should match exactly, not even a comma difference, or a comment difference.

If you find that 1) all the code on your IDE passes check50 2) all the (latest) submitted code matches your IDE code exactly and 3) Gradebook is getting a different result from check50, you need to wait the required 2 weeks from the date of last submission to contact the staff. If you have already contacted the staff, then should probably wait two weeks before you contact them again.

  • 1
    Thanks! I've resubmitted pset1 and I will give it 2 weeks! I've also checked it over with check50. Is it OK for me to submit pset2 or should I wait the 2 weeks before I resubmit it? Aug 31, 2016 at 20:43
  • 1
    I'd say submit pset2 if you're done with it. Aug 31, 2016 at 21:54
  • I submitted pset2 and received a 0, even though I used no snippets of code and cited all stackexchange websites I looked at. Sep 5, 2016 at 22:53
  • Has your pset1 been graded? Sep 6, 2016 at 0:13
  • Yes, and it too received a 0. Sep 6, 2016 at 17:54

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