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Concept guides/Arrays and strings/Set operations

CodingArrays and strings

Set operations

Easy5 min read

Questions it teaches

Roster changesEasy11 min Shared distinct tagsEasy10 min Symmetric differenceEasy11 min Union of distinct episodesEasy10 min Playlist contains requirementsEasy10 min Common songs across playlistsMedium15 min Countries that buy but never refundMedium11 min Every date something happenedMedium11 min

Related

Arrays and strings Searching and sorting Designing data structures Backtracking and games Dynamic programming Data and ML code Front-end code

Leads to: Searching and sorting

Sorting algorithms3 min Two pointers3 min

Leads to: Designing data structures

Queues, deques & ring buffers3 min Database deduplication3 min

Leads to: Backtracking and games

Recursion & backtracking3 min Game theory & Grundy3 min

Leads to: Dynamic programming

Dynamic programming: 2D & strings3 min Dynamic programming: 1D3 min

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