Time: 0:00
Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).
This bug belongs to the mutation and copying bugs pattern
Assignment does not copy, a shallow copy still shares its contents, and mutating methods return None.
What went wrong: removing 2 moves 4 into its place. The loop then moves on to the next position, so 4 is never checked.
The fix: return [n for n in nums if n % 2 != 0]
Remember: do not remove items from a list while looping over it. Build a new list.
The pattern behind it: mutation and copying bugs.
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<iframe src="https://trybughunt.com/embed/b309ba54-522d-4670-aa53-4891f1a842a6" title="Debugging challenge: Removing even numbers leaves one behind" width="100%" height="580" loading="lazy" style="border:1px solid #d4d4d8;border-radius:12px;max-width:760px"></iframe>
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