Data Structures and Algorithms · Hashing

Hash tables

Mapping keys to array slots via a hash function for near-constant-time lookup.

Also known as: hash maps, dictionaries, chaining, open addressing.

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• Linked lists: Nodes scattered in memory, each pointing to the next, trading fast indexing for cheap insertion.

Related topics

• String matching algorithms: Finding all occurrences of a pattern inside a larger text faster than checking every position.
• Arrays: A fixed-layout, contiguous block of memory where any index is reached in constant time.