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: new Array(length) creates sparse empty slots. Array.prototype.map() skips uninitialized slots entirely.
The fix: Use Array.from() with a mapping function to initialize all elements: Array.from({ length }, (_, i) => i)
Remember: In JavaScript, array.map() ignores empty slots in sparse arrays.
The pattern behind it: logic errors.
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<iframe src="https://trybughunt.com/embed/9e4399fe-75f3-4ff0-bca9-28aa388f8067" title="Debugging challenge: Array constructor with map skips uninitialized empty slots" 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/9e4399fe-75f3-4ff0-bca9-28aa388f8067">TryBugHunt</a></p>