Time: 0:00
Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).
This bug belongs to the logic errors pattern
The wrong operator, an inverted condition, a formula the right way round but backwards.
What went wrong: Binary floating-point arithmetic cannot represent certain decimal values precisely, producing tiny rounding artifacts.
The fix: Round the calculation result to two decimal places: round(gross_amount - processing_fee, 2)
Remember: In Python, round floating-point currency and decimal arithmetic to prevent precision artifacts.
The pattern behind it: logic errors.
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<iframe src="https://trybughunt.com/embed/c44d1ff5-65e5-4c3e-9972-037fb4f016b8" title="Debugging challenge: Floating point fee calculation leaves precision artifact" width="100%" height="580" loading="lazy" style="border:1px solid #d4d4d8;border-radius:12px;max-width:760px"></iframe>
<p style="font-size:14px">Debugging challenge from <a href="https://trybughunt.com/challenges/c44d1ff5-65e5-4c3e-9972-037fb4f016b8">TryBugHunt</a></p>