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Collections & Immutability Discipline
DSA

Collections & Immutability Discipline

Master Array Patterns concepts for competitive exams.

HashMap<Integer, Integer> map = new HashMap<>();
Map<Integer, Integer> valueToIndex = new HashMap<>();

Data Structure Intent

Use CaseStructure
Fast lookupHashMap
Unique valuesHashSet
FIFOQueue
LIFODeque
Ordered keysTreeMap

Always explain why in interviews.

Immutability Signal

public int findMax(final int[] numbers)

My Private Notes

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