We study three comparison-based problems related to multisets in the cache-oblivious model: Duplicate elimination, multisorting and finding the most frequent element (the mode). We are interested in minimizing the cache complexity (or number of cache misses) of algorithms for these problems in the context under which cache size and block size are unknown. We give algorithms with cache complexities within a constant factor of the optimal for all the problems. In the case of determining the mode, the optimal algorithm is randomized as the deterministic algorithm differs from the lower bound by a sublogarithmic factor. We can achieve optimality either with a randomized method or if given, along with the input, lg lg of relative frequency of the mode with a constant additive error. © Springer-Verlag Berlin Heidelberg 2005.
Cache-oblivious comparison-based algorithms on multisets / Arash, Farzan; Paolo, Ferragina; Franceschini, Gianni; J., Ian Munro. - STAMPA. - 3669:(2005), pp. 305-316. (Intervento presentato al convegno ESA tenutosi a Palma de Mallorca) [10.1007/11561071_29].
Cache-oblivious comparison-based algorithms on multisets
FRANCESCHINI, GIANNI;
2005
Abstract
We study three comparison-based problems related to multisets in the cache-oblivious model: Duplicate elimination, multisorting and finding the most frequent element (the mode). We are interested in minimizing the cache complexity (or number of cache misses) of algorithms for these problems in the context under which cache size and block size are unknown. We give algorithms with cache complexities within a constant factor of the optimal for all the problems. In the case of determining the mode, the optimal algorithm is randomized as the deterministic algorithm differs from the lower bound by a sublogarithmic factor. We can achieve optimality either with a randomized method or if given, along with the input, lg lg of relative frequency of the mode with a constant additive error. © Springer-Verlag Berlin Heidelberg 2005.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.