Time: 0:00
Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).
This bug belongs to the type errors pattern
Totals that concatenate, sorts that put 10 before 9, comparisons that refuse to run.
What went wrong: split("") gives text like "1". 0 + "1" joins them instead of adding.
The fix: .reduce((sum, digit) => sum + Number(digit), 0)
Remember: + with text joins in JavaScript. Convert to Number first.
The pattern behind it: type errors.
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<iframe src="https://trybughunt.com/embed/ea6492f9-4091-4e28-b73d-33a5cf966070" title="Debugging challenge: Digit sum gives "0123" instead of 6" 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/ea6492f9-4091-4e28-b73d-33a5cf966070">TryBugHunt</a></p>