1236
mediumGrind 75

Permutations

This one has lots of possibilities, and it's really testing whether you can explore them systematically. Interviewers love it because it reveals your structured exploration and your edge-case discipline. Backtracking gets messy when you don't undo state cleanly; be disciplined about it.

Arrays & HashingBacktracking
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1Array Arrangementsmedium
Based onLeetCode

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