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What does "hash set" mean in programming?
hash set is one of the most common terms in software development. This guide explains what it means, how it is used in practice, and why it matters, with real examples from the developer world.
Definition
A set implementation backed by a hash table, providing O(1) average time for add, remove, and contains operations. Elements must be hashable. HashSet is the class name in Java; Python's built-in set uses the same principle.
Example
"HashSet<String> seen = new HashSet<>(); if (seen.contains(id)) { /* duplicate */ }"
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