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JavaScriptLow-Medium

Use Set/Map for O(1) Lookups

Convert arrays to Set/Map for repeated membership checks.

javascriptsetmapdata-structuresperformance

Code Comparison

•Incorrect (O(n) per check):typescript
•Correct (O(1) per check):typescript

Why This Matters

Impact: O(n) to O(1). This optimization is classified as LOW-MEDIUM priority for production applications.

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