Tested Against the Sample Input Only
The brief gives you one example. Your marker has a suite. Empty input, wrong type, boundary value — that is where a working program falls over.
THE REAL PROBLEM
Why Does Working Code Still Get a Low Grade?
It compiles. It produces the expected output for the sample input in the brief. You submit it, and it comes back somewhere in the fifties with a comment about robustness and documentation.
Your tutor does not run the sample input. They run an empty file, a negative number, a duplicate key, a string where an integer belongs — and then they read your code to see whether a person could maintain it. Both of those are marked, and neither is what students test against.
Running is the entry requirement, not the assignment. What gets marked is how it behaves when the input is wrong and how well it reads when it is right.
Send My Repo
No Comments, No README
Documentation is often ten to twenty per cent of the rubric outright. It takes an hour and students skip it because the code already works.
A Solution You Cannot Explain
Copied from a forum at 2am and it fixed the error. In the demo you get asked why you chose that data structure, and there is no answer.
Complexity Never Considered
Nested loops that finish instantly on ten records and time out on ten thousand. Second and third year papers mark this explicitly.
One Commit, Named “final”
Version control is assessed in most team papers. A single commit the night before tells your marker exactly how the project ran.
Similarity Checks Read Code Too
Code similarity tools compare structure, not just text. Renaming variables changes nothing, and a shared solution shows up in both submissions.