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 representation cannot represent 0.1, 0.2, or 0.3 exactly, producing precision artifacts.
The fix: Round the subtraction result to two decimal places: round(price - discount, 2)
Remember: In Python, always round floating-point currency and decimal arithmetic.
The pattern behind it: logic errors.
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<iframe src="https://trybughunt.com/embed/7436fa85-66b7-46be-bbb3-602888efc8a0" title="Debugging challenge: Floating point subtraction in price calculator 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/7436fa85-66b7-46be-bbb3-602888efc8a0">TryBugHunt</a></p>