array-hash - C++ implementation of a fast and memory efficient hash map and hash set specialized for strings

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Cache conscious hash map and hash set for strings based on the "Cache-conscious collision resolution in string hash tables." (Askitis Nikolas and Justin Zobel, 2005) paper. You can find some details regarding the structure here. Thanks to its cache friendliness, the structure provides fast lookups while keeping a low memory usage. The main drawback is the rehash process which is a bit slow and need some spare memory to copy the strings from the old hash table to the new hash table (it can’t use std::move as the other hash tables using std::string as key).

https://github.com/Tessil/array-hash

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