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JavaScriptLow-Medium

Build Index Maps for Repeated Lookups

Multiple `.find()` calls by the same key should use a Map.

javascriptmapindexingoptimizationperformance

Code Comparison

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

Why This Matters

Impact: 1M ops to 2K ops. This optimization is classified as LOW-MEDIUM priority for production applications.

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