On Sharing, Memoization, and Polynomial Time

Authors Martin Avanzini, Ugo Dal Lago

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Martin Avanzini
Ugo Dal Lago

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Martin Avanzini and Ugo Dal Lago. On Sharing, Memoization, and Polynomial Time. In 32nd International Symposium on Theoretical Aspects of Computer Science (STACS 2015). Leibniz International Proceedings in Informatics (LIPIcs), Volume 30, pp. 62-75, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2015)


We study how the adoption of an evaluation mechanism with sharing and memoization impacts the class of functions which can be computed in polynomial time. We first show how a natural cost model in which lookup for an already computed result has no cost is indeed invariant. As a corollary, we then prove that the most general notion of ramified recurrence is sound for polynomial time, this way settling an open problem in implicit computational complexity.
  • implicit computational complexity
  • data-tiering
  • polynomial time


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