Time: 0:00
Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).
This bug belongs to the infinite loops pattern
The tab freezes, nothing prints, and the loop condition never becomes false.
What went wrong: i only goes up when the letter is a capital. On "a", i never moves, so the loop checks "a" forever.
The fix: move i = i + 1 outside the if.
Remember: the loop's step must run every time, whatever the if decides.
The pattern behind it: infinite loops.
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<iframe src="https://trybughunt.com/embed/4fe90d03-616f-42e9-a5fd-98967602bf1c" title="Debugging challenge: Counting capitals freezes on a lowercase letter" 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/4fe90d03-616f-42e9-a5fd-98967602bf1c">TryBugHunt</a></p>