Ara es mostren els items 1-19 de 19

  • A Fibonacci sequence for linear structures with two types of components 

    Freixas Bosch, Josep; Molinero Albareda, Xavier; Roura Ferret, Salvador (2009-07-23)
    Report de recerca
    Accés obert
    We investigate binary voting systems with two types of voters and a hierarchy among the members in each type, so that members in one class have more influence or importance than members in the other class. The purpose ...
  • An Improved master theorem for divide-and-conquer recurrences 

    Roura Ferret, Salvador (1997-01)
    Report de recerca
    Accés obert
    We present a new master theorem for the study of divide-and-conquer recursive definitions, which improves the old one in several aspects. In particular, it provides more information, frees us from technicalities like ...
  • Better feedback for educational online judges 

    Mani, Anaga; Venkataramani, Divya; Petit Silvestre, Jordi; Roura Ferret, Salvador (SciTePress, 2014)
    Text en actes de congrés
    Accés obert
    The verdicts of most online programming judges are, essentially, binary: the submitted codes are either “good enough” or not. Whilst this policy is appropriate for competitive or recruitment platforms, it can hinder the ...
  • Complete voting systems with two types of voters: weightedness and counting 

    Freixas Bosch, Josep; Molinero Albareda, Xavier; Roura Ferret, Salvador (2012)
    Article
    Accés restringit per decisió de l'autor
    We investigate voting systems with two classes of voters, for which there is a hierarchy giving each member of the stronger class more influence or important than each member of the weaker class. We deduce for voting systems ...
  • Digital access to comparison-based tree data structures and algorithms 

    Roura Ferret, Salvador (1999-07)
    Report de recerca
    Accés obert
    This paper presents a simple method to build tree data structures which achieve just O(log N) visited nodes and O(D) compared digits (bits or bytes) per search or update, where N is the number of keys and D is the length ...
  • Improving mergesort for linked lists 

    Roura Ferret, Salvador (1999-04)
    Report de recerca
    Accés obert
    We present a highly tuned mergesort algorithm that improves the cost bounds when used to sort linked lists of elements. We provide empirical comparisons of our algorithm with other mergesort algorithms. The paper also ...
  • Joc d’estructures de dades i algorismes 

    Duch Brown, Amalia; Petit Silvestre, Jordi; Rodríguez Carbonell, Enric; Roura Ferret, Salvador (Universitat Politècnica de Catalunya. Institut de Ciències de l'Educació, 2014-04-24)
    Text en actes de congrés
    Accés obert
    L'activitat consisteix en la implementació d'un jugador per a un joc d'ordinador. L'objectiu és que els estudiants hi apliquin els algorismes i estructures de dades explicats en el curs. Un joc consisteix en un tauler on ...
  • Jutge.org 

    Giménez, Omer; Petit Silvestre, Jordi; Roura Ferret, Salvador (2011)
    Report de recerca
    Accés obert
    Jutge.org is an open access educational online programming judge where students can try to solve more than 800 problems using 22 programming languages. The verdict of their solutions is computed using exhaustive test sets ...
  • Jutge.org: characteristics and experiences 

    Petit Silvestre, Jordi; Roura Ferret, Salvador; Carmona Vargas, Josep; Cortadella Fortuny, Jordi; Duch Brown, Amalia; Giménez, Omer; Mani, Anaga; Mas Rovira, Jan; Rodríguez Carbonell, Enric; Rubio Gimeno, Alberto; San Pedro Martín, Javier de; Venkataramani, Divya (2017-07-04)
    Article
    Accés obert
    Jutge.org is an open educational online programming judge designed for students and instructors, featuring a repository of problems that is well organized by courses, topics and difficulty. Internally, Jutge.org uses a ...
  • Lists revisited: cache conscious STL lists 

    Frias Moya, Leonor; Petit Silvestre, Jordi; Roura Ferret, Salvador (2005-11)
    Report de recerca
    Accés obert
    We present three cache conscious implementations of STL standard compliant lists. Up to now, one could either find simple double linked list implementations that easily cope with standard strict requirements, or theoretical ...
  • Minimal representations for majority games 

    Freixas Bosch, Josep; Molinero Albareda, Xavier; Roura Ferret, Salvador (2007-02)
    Report de recerca
    Accés obert
    This paper presents some new results about majority games. Isbell (1959) was the first to find a majority game without a minimum normalized representation; he needed 12 voters to construct such a game. Since then, it has ...
  • Multikey Quickselect 

    Frias Moya, Leonor; Roura Ferret, Salvador (2009-07)
    Report de recerca
    Accés obert
    In this paper we introduce Multikey Quickselect: an efficient, in-place, and easy to implement algorithm for the selection problem for strings. We present several variants of our basic algorithm, which apply to two different ...
  • On the competitiveness of the move-to-front rule 

    Roura Ferret, Salvador; Martínez Parra, Conrado (1996-11)
    Report de recerca
    Accés obert
    We consider the list access problem and show that one questionable assumption in the original cost model presented by Sleator and Tarjan (Amortized Efficiency of List Update and Paging Rules, CACM, 28(2):202-208, ...
  • Optimal and nearly optimal weighted skip lists 

    Martínez Parra, Conrado; Roura Ferret, Salvador (1995-01-01)
    Report de recerca
    Accés obert
    We consider the problem of building a static (i.e. no updates are performed) skip list of n elements, given these n elements and the corresponding access probabilities or weights. We develop a dynamic programming algorithm ...
  • Optimal sampling strategies in quicksort and quickselect 

    Martínez Parra, Conrado; Roura Ferret, Salvador (1998-01)
    Report de recerca
    Accés obert
    It is well-known that the performance of quicksort may substantially be improved by selecting the median of a sample of three elements as the pivot of each partitioning stage. This variant makes more unlikely the ...
  • Programación-1: Una asignatura orientada a la resolución de problemas 

    Petit Silvestre, Jordi; Roura Ferret, Salvador (2009-06-20T11:38:12Z)
    Text en actes de congrés
    Accés obert
    En este artículo presentamos el nuevo método docente de la asignatura Programació-1 en la Facultat d’Informàtica de Barcelona de la Universitat Politècnica de Catalunya, y damos cuenta de los resultados obtenidos durante ...
  • Quad-kd trees: A general framework for kd trees and quad trees 

    Bereczky, Nikolett; Duch Brown, Amalia; Németh, Krisztián; Roura Ferret, Salvador (2016-02-22)
    Article
    Accés obert
    We introduce the quad-kd tree: a general purpose and hierarchical data structure for the storage of multidimensional points. Quad-kd trees include point quad trees and kd trees as particular cases and therefore they could ...
  • Randomization of search trees by subtree size 

    Martínez Parra, Conrado; Roura Ferret, Salvador (1996-01)
    Report de recerca
    Accés obert
    In this paper we present probabilistic algorithms over random binary search trees such that: a) the insertion of a set of keys in any fixed order into an initially empty tree produces always a random tree; b) the deletion ...
  • Randomized binary search trees 

    Martínez Parra, Conrado; Roura Ferret, Salvador (1997-01)
    Report de recerca
    Accés obert
    In this paper we present randomized algorithms over binary search trees such that: a) the insertion of a set of keys, in any fixed order, into an initially empty tree always produces a random binary search tree; b) the ...