Constant Access Time ?
نویسندگان
چکیده
We generalize Cuckoo Hashing 23] to d-ary Cuckoo Hashing and show how this yields a simple hash table data structure that stores n elements in (1 +) n memory cells, for any constant > 0. Assuming uniform hashing, accessing or deleting table entries takes at most d = O(ln 1) probes and the expected amortized insertion time is constant. This is the rst dictionary that has worst case constant access time and expected constant update time, works with (1 +) n space, and supports satellite information. Experiments indicate that d = 4 choices suuce for 0:03. We also describe variants of the data structure that allow the use of hash functions that can be evaluted in constant time.
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