Code reviewHardcr-g337

Subject Floating pointLevel Senior–Staff~22 minCommon in Code quality & review interviewsIndustries Software development

Question

Review this Python that verifies a posted-then-reversed fee leaves a large account balance unchanged, as an end-of-day integrity check.

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Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewpython

1def apply_fee(balance, fee):2    return balance + fee3 4def reverse_fee(balance, fee):5    return balance - fee6 7def net_zero(balance, fee):8    # balance like 1e16, fee like 0.079    after = apply_fee(balance, fee)10    restored = reverse_fee(after, fee)11    return restored == balance12 13# net_zero(1e16, 0.07) -> expected True

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