Minimean optimal key arrangements in hash tables


For an open-addressing hash functionh and a setA ofn keys, letCh(A) be the expected retrieval cost when the keys are arranged to minimize the expected retrieval cost in a full table. It is shown that, asymptotically for largen, whenh satisfies a certain doubly dispersive property, as is the case for double hashing,C h (A)=0(1) with probability 1 − 0(1) for a randomA.

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This research was supported in part by the National Science Foundation under Grant DCR-8308109.

Communicated by C. K. Wong.

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Yao, A.C.-. Minimean optimal key arrangements in hash tables. Algorithmica 14, 409–428 (1995).

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Key words

  • Assignment problem
  • Double hashing
  • Hash tables
  • Key arrangement
  • Retrieval