Lecture Notes in Computer Science 3580 CommencedPublicationin1973 FoundingandFormerSeriesEditors: GerhardGoos,JurisHartmanis,andJanvanLeeuwen EditorialBoard DavidHutchison LancasterUniversity,UK TakeoKanade CarnegieMellonUniversity,Pittsburgh,PA,USA JosefKittler UniversityofSurrey,Guildford,UK JonM.Kleinberg CornellUniversity,Ithaca,NY,USA FriedemannMattern ETHZurich,Switzerland JohnC.Mitchell StanfordUniversity,CA,USA MoniNaor WeizmannInstituteofScience,Rehovot,Israel OscarNierstrasz UniversityofBern,Switzerland C.PanduRangan IndianInstituteofTechnology,Madras,India BernhardSteffen UniversityofDortmund,Germany MadhuSudan MassachusettsInstituteofTechnology,MA,USA DemetriTerzopoulos NewYorkUniversity,NY,USA DougTygar UniversityofCalifornia,Berkeley,CA,USA MosheY.Vardi RiceUniversity,Houston,TX,USA GerhardWeikum Max-PlanckInstituteofComputerScience,Saarbruecken,Germany Luís Caires Giuseppe F. Italiano Luís Monteiro Catuscia Palamidessi MotiYung (Eds.) Automata, Languages and Programming 32nd International Colloquium, ICALP 2005 Lisbon, Portugal, July 11-15, 2005 Proceedings 1 3 VolumeEditors LuísCaires UniversidadeNovadeLisboa,DepartamentodeInformatica 2829-516Caparica,Portugal E-mail:[email protected] GiuseppeF.Italiano UniversitádiRoma“TorVergata” DipartimentodiInformatica,SistemieProduzione ViadelPolitecnico1,00133Roma,Italy E-mail:[email protected] LuísMonteiro UniversidadeNovadeLisboa,DepartamentodeInformatica 2829-516Caparica,Portugal E-mail:[email protected] CatusciaPalamidessi INRIAFutursandLIX,ÉcolePolytechnique ruedeSaclay,91128Palaiseau,France E-mail:[email protected] MotiYung RSALaboratoriesandColumbiaUniversity ComputerScienceDepartment 1214AmsterdamAv.,NewYork,NY10027,USA E-mail:[email protected] LibraryofCongressControlNumber:2005928673 CRSubjectClassification(1998):F,D,C.2-3,G.1-2,I.3,E.1-2 ISSN 0302-9743 ISBN-10 3-540-27580-0SpringerBerlinHeidelbergNewYork ISBN-13 978-3-540-27580-0SpringerBerlinHeidelbergNewYork Thisworkissubjecttocopyright.Allrightsarereserved,whetherthewholeorpartofthematerialis concerned,specificallytherightsoftranslation,reprinting,re-useofillustrations,recitation,broadcasting, reproductiononmicrofilmsorinanyotherway,andstorageindatabanks.Duplicationofthispublication orpartsthereofispermittedonlyundertheprovisionsoftheGermanCopyrightLawofSeptember9,1965, initscurrentversion,andpermissionforusemustalwaysbeobtainedfromSpringer.Violationsareliable toprosecutionundertheGermanCopyrightLaw. SpringerisapartofSpringerScience+BusinessMedia springeronline.com ©Springer-VerlagBerlinHeidelberg2005 PrintedinGermany Typesetting:Camera-readybyauthor,dataconversionbyScientificPublishingServices,Chennai,India Printedonacid-freepaper SPIN:11523468 06/3142 543210 Preface The32ndInternationalColloquiumonAutomata,LanguagesandProgramming (ICALP 2005) was held in Lisbon, Portugal from July 11 to July 15, 2005. These proceedings contain all contributed papers presented at ICALP 2005, to- getherwiththepapersbytheinvitedspeakersGiuseppeCastagna(ENS),Leonid Libkin (Toronto), John C. Mitchell (Stanford), Burkhard Monien (Paderborn), and Leslie Valiant (Harvard). The program had an additional invited lecture by Adi Shamir (Weizmann Institute) which does not appear in these proceedings. ICALP is a series of annual conferences of the European Association for Theoretical Computer Science (EATCS). The first ICALP took place in 1972. Thisyear,theICALPprogramconsistedoftheestablishedtrackA(focusingon algorithms, automata, complexity and games) and track B (focusing on logic, semantics and theory of programming), and innovated on the structure of its traditional scientific program with the inauguration of a new track C (focusing on security and cryptography foundation). In response to a call for papers, the Program Committee received 407 sub- missions, 258 for track A, 75 for track B and 74 for track C. This is the highest number of submitted papers in the history of the ICALP conferences. The Pro- gram Committees selected 113 papers for inclusion in the scientific program. In particular, the Program Committee for track A selected 65 papers, the Pro- gram Committee for track B selected 24 papers, and the Program Committee for track C selected 24 papers. All the work of the Program Committees was done electronically. ICALP 2005 was held in conjunction with the Annual ACM International Symposium on Principles and Practice of Declarative Programming (PPDP2005).Additionally,thefollowingworkshopswereheldassatelliteevents ofICALP2005:the2ndWorkshoponAutomatedReasoningforSecurityProto- col Analysis (ARSPA), the 1st International Workshop on Verification of COn- current Systems with dynaMIC Allocated Heaps (COSMICAH), the 1st Inter- nationalWorkshoponNewDevelopmentsinComputationalModels(DCM),the 4thInternationalWorkshoponParallelandDistributedMethodsinVerification (PDMC),the4thInternationalWorkshoponProofTheory,Computation,Com- plexity(PCC),theWorkshoponStructuresandDeduction—TheQuestforthe EssenceofProofs(DS),the2ndWorkshoponStructuralOperationalSemantics (SOS), and the Workshop on Semigroups and Automata (WSA). We wish to thank all authors who submitted papers for consideration, the Program Committees for their hard work, as well as the external reviewers who assisted the Program Committees in the evaluation process. We thank the sponsors and the Gulbenkian Foundation of Lisbon for host- ing ICALP 2005. We are also grateful to the Department of Informatics of the VI Preface Faculty of Sciences and Technology, New University of Lisbon, in particular the administrative office and the technical support service. Lastbutnotleast,wewouldliketothankAndreiVoronkovforprovidingthe conferencemanagementsoftwareEasyChair.Itwasofgreathelpinhandlingthe submissions and the electronic PC meeting. Lu´ıs Caires Giuseppe F. Italiano Lu´ıs Monteiro Catuscia Palamidessi Moti Yung Organization Program Committee Track A Lars Arge, Duke University, USA Giorgio Ausiello, University of Rome“La Sapienza”, Italy Surender Baswana, Max-Planck-Institut fu¨r Informatik, Saarbru¨cken, Germany Hans Bodlaender, University of Utrecht, The Netherlands V´eronique Bruy`ere, University of Mons-Hainaut, Belgium Adam Buchsbaum, AT&T Labs Research, USA Josep Diaz, Universitat Polit`ecnica de Catalunya, Spain David Eppstein, University of Irvine, USA Andrew Goldberg, Microsoft, USA Monika Henzinger, Google and ETH Lausanne, Switzerland Giuseppe F. Italiano, University of Rome“Tor Vergata”, Italy (Chair) Marios Mavronicolas, University of Cyprus, Cyprus Peter Bro Miltersen, University of Aarhus, Denmark Mike Paterson, University of Warwick, UK Dominique Perrin, Universit´e de Marne la Vall´ee, France Seth Pettie, Max-Planck-Institut fu¨r Informatik, Saarbru¨cken, Germany Yuval Rabani, Technion, Israel Antonio Restivo, University of Palermo, Italy Jos´e Rolim, University of Geneva, Switzerland Dorothea Wagner, University of Karlsruhe, Germany Tandy Warnow, University of Texas at Austin, USA Christos Zaroliagis, CTI and University of Patras, Greece Track B Kenichi Asai, Ochanomizu University, Japan Jos Baeten, Eindhoven University of Technology, The Netherlands Peter Buneman, University of Edinburgh, UK Zoltan Esik, University of Szeged, Hungary and Rovira University, Spain Javier Esparza, University of Stuttgart, Germany Marcelo Fiore, Christ’s College and University of Cambridge, UK Manuel Hermenegildo, Universidad Polit`ecnica de Madrid, Spain Delia Kesner, Universit´e Paris VII, France Kim Guldstrand Larsen, University of Aalborg, Denmark Gopalan Nadathur, University of Minnesota, USA VIII Organization Uwe Nestmann, EPFL, Switzerland Catuscia Palamidessi, INRIA, France (Chair) Amr Sabry, University of Indiana, USA Davide Sangiorgi, Universita` di Bologna, Italy Roberto Segala, Universit`a di Verona, Italy Harald Søndergaard, University of Melbourne, Australia Track C David Basin, ETH Zurich, Switzerland Christian Cachin, IBM Research, Switzerland Alfredo De Santis, Universita` di Salerno, Italy Cynthia Dwork, Microsoft Research, USA Matt Franklin, U.C. Davis, USA Michael Goodrich, U.C. Irvine, USA Andrew D. Gordon, Microsoft Research, UK Roberto Gorrieri, Universita` di Bologna, Italy Yuval Ishai, Technion, Israel Phil MacKenzie, DoCoMo Labs, USA Tatsuaki Okamoto, NTT Labs, Japan David Pointcheval, ENS Paris, France Tal Rabin, IBM Research, USA Omer Reingold, Weizmann Institute, Israel Adi Rosen, Technion, Israel Amit Sahai, UCLA, USA Andre Scedrov, University of Pennsylvania, USA Igor Shparlinski, Macquarie University, Australia Nigel Smart, University of Bristol, UK Moti Yung, Columbia University and RSA Laboratories, USA (Chair) Organizing Committee Lu´ıs Caires, Conference Co-chair Lu´ıs Monteiro, Conference Co-chair Anto´nio Ravara, Workshops Co-chair Vasco Vasconcelos, Workshops Co-chair Margarida Mamede Jo˜ao Costa Seco Jos´e Pacheco Organization IX List of External Referees Track A Karen Aardal Moses Charikar Gudmund Frandsen Scott Aaronson Hubie Chen Alan Frieze Saurabh Aggarwal Joseph Cheriyan Andrea Frosini Marjan van den Akker Janka Chlebikova Marco Gaertler Cyril Allauzen Bogdan Chlebus Martin Gairing Jean-Paul Allouche Christian Choffrut Emden Gansner Luca Allulli George Christodoulou Naveen Garg Carme Alvarez Serafino Cicerone William Ian Gasarch Andris Ambainis Julien Cl´ement Leszek Gasieniec Marcella Anselmo Andrea Clementi Georgiadis Georgios Sanjeev Arora Eric de La Clergerie Kostis Georgiou Albert Atserias Bruno Codenotti Arkadeb Ghosal Vincenzo Auletta Edith Cohen Dora Giammarresi Jose Balcazar Anne Condon Raffaele Giancarlo Jeremy Barbay Pier Francesco Cortese Aristides Gionis Amotz Bar-Noy Stefano Crespi-Reghizzi Ashish Goel Tugkan Batu Peter Damaschke Paul Golberg Michael Baur Fabrizio d’Amore Robert G¨orke Marie-Pierre B´eal Camil Demetrescu Fabrizio Grandoni Luca Becchetti Kedar Dhamdhere Serge Grigorieff Philip Bille Christoph Dorr Alexander Grigoriev Yvonne Bleischwitz Petros Drineas Joachim Gudmundsson Maria J. Blesa Christoph Durr Rachid Guerraoui Avrim Blum Stephan Eidenbenz Dan Gusfield Luc Boasson Amr Elmasry Gus Gutoski Vincenzo Bonifaci Thomas Erlebach M. Hajiaghayi Paola Bonizzoni Alex Fabrikant Magnus M. Halldorsson Vasco Brattka Rolf Fagerberg Kristoffer Hansen Gerth Stølting Brodal Jacques Farr´e Sariel Har-Peled Peter Buergisser Lene Favrholdt Ramesh Hariharan Harry Buhrman Rainer Feldmann Herman Haverkort Luciana S. Buriol Stephen A. Fenner Illya V. Hicks Costas Busch Antonio Fernandez Mika Hirvensalo Cristian S. Calude Henning Fernau John Hitchcock Massimiliano Caramia Paolo Ferragina Martin Holzer Jean Cardinal Jiri Fiala Han Hoogeveen Olivier Carton Irene Finocchi Peter Hoyer Patrick Cegielski Fedor Fomin Juraj Hromkovic Julien Cervelle Lance Fortnow Cor Hurkens J.-M. Champarnaud Dimitris Fotakis Lucian Ilie Sunil Chandran Paolo G. Franciosa Costas Iliopoulos X Organization Piotr Indyk Thierry Lecroq Philippe Moser Garud Iyengar Stefano Leonardi Anca Muscholl Kamal Jain Pierre Leone Umberto Nanni Petr Janˇcar Xiang-Yang Li Konstantinos Nedas Klaus Jansen Paolo Liberatore Mark-Jan Nederhof Mark Jerrum Christian Liebchen Jaroslav Nesetril David Johnson Michael Loizos Frank Neven Adrian Johnstone Thomas Luecking Sotiris Nikoletseas Marcin Jurdzinski George Lueker John Noga Erich Kaltofen Alejandro Maas Rasmus Pagh Juhani Karhum¨aki Marina Madonia Jakob Illeborg Pagter Anna Karlin Malik Magdon-Ismail Rina Panigrahy Marek Karpinski Frederic Magniez Anindya Patthak Claire Kenyon Mohammad Mahdian Christian N.S. Pedersen Richard Kenyon Christos Makris David Peleg Iordanis Kerenidis Sebastian Maneth Sriram Pemmaraju Leonid Khachiyan Alberto Spaccamela Giovanni Pighizzini Rohit Khandekar Maurice Margenstern Jean-Eric Pin Pekka Kilpelainen Vangelis Markakis Giuseppe Pirillo Lefteris Kirousis Chip Martel Nadia Pisanti Ralf Klasing Giancarlo Mauri Andrzej Proskurowski Rolf Klein Jacques Mazoyer J. Radhakrishnan Bettina Klinz Pierre McKenzie Harald Raecke Adam Klivans Frank McSherry Mathieu Raffinot Pascal Koiran Steffen Mecke Srinivasa Rao Jochen Konemann Dieter van Melkebeek David Rappaport Spyros Kontogiannis Carlo Mereghetti Jean-Franc¸ois Raskin Guy Kortsarz Wolfgang Merkle S.S. Ravi Arie Koster Ramgopal Mettu John Reif Manolis Koubarakis Ulrich Meyer Jan Reimann Elias Koutsoupias Dimitrios Michail Omer Reingold Daniel Kral Christian Michaux Eric R´emila Evangelos Kranakis Filippo Mignosi Christophe Reutenauer Dieter Kratsch Vahab Mirrokni Michel Rigo Michael Krivelevich Michael Mitzenmacher Adi Rosen Ravi Kumar Shuichi Miyazaki Martin Rotteler Viraj Kumar Kousha MoaveniNejad Tim Roughgarden Dietrich Kuske Mehryar Mohri Gilles Roussel Shay Kutten Burkhard Monien Alexander Russell Gregory Lafitte Cris Moore Jacques Sakarovitch Jens Lagergren Shlomo Moran Peter Sanders Sophie Laplante Burkhard Morgenstern Pierluigi San Pietro Michel Latteux Kenichi Morita Miklos Santha Luigi Laura Gabriel Moruz Martin Sauerhoff Van Bang Le Thomas Moscibroda Guido Schaefer Organization XI Thomas Schank Paul Spirakis Kasturi Varadarajan Christian Schindelhauer Venkatesh Srinivasan Vijay V. Vazirani Torsten Schlieder Ludwig Staiger S. Venkatasubramanian Anita Sch¨obel Yannis Stamatiou Adrian Vetta Sylvain Schmitz Cliff Stein Eric Vigoda E´tienne Schramm David Steurer Emanuele Viola Frank Schulz Leen Stougie Rakesh V. Vohra Elizabeth Scott Howard Straubing Heribert Vollmer Luc Segoufin Martin Strauss Nicolai Vorbjov Helmut Seidl K.S. Sudeep Osamu Watanabe Pranab Sen Peng Sun Pascal Weil G´eraud S´enizergues Maxim Sviridenko Klaus Wich Maria Serna Mario Szegedy Peter Widmayer Rocco Servedio Claude Tadonki Jef Wijsen Jeffrey Shallit Kunal Talwar Gerhard Woeginger Micha Sharir Gerard Tel Alexander Wolff Peter Shor Dimitrios Thilikos Deng Xiaotie Riccardo Silvestri Wolfgang Thomas Hiroaki Yamamoto Alistair Sinclair Karsten Tiemann Mihalis Yannakakis Spiros Skiadopoulos Luca Trevisan Norbert Zeh Martin Skutella Panayiotis Tsaparas Li Zhang Roberto Solis-Oba Kostas Tsichlas Wieslaw Zielonka Robert Spalek Marc Uetz Uri Zwick Klaus Ambos Spies Ugo Vaccaro Track B Elvira Albert Benedikt Bollig Manuel Carro Thorsten Altenkirch Johannes Borgstr¨om D. Caucal Rajeev Alur Dragan Boˇsnaˇcki Witold Charatonik Sergio Antoy Debora Botturi Krishnendu Chatterjee Andr´e Arnold Ahmed Bouajjani Chiyan Chen Benjamin Aziz Patricia Bouyer James Cheney Brian Babcock Julian Bradfield Tom Chothia James Bailey Mario Bravetti Horatiu Cirstea Vincent Balat Franck van Breugel Rance Cleaveland Jos´e Balc´azar S´ebastien Briais John Cochran Michael Baldamus Geoffrey Brown Thomas Colcombet Jiri Barnat Glenn Bruns Andrea Corradini Gerd Behrmann Antonio Bucciarelli Flavio Corradini Martin Berger Francisco Bueno Alin Deutsch Jan Bergstra Nadia Busi Silvano Dal-Zilio Luca Bianco Lu´ıs Caires Vincent Danos Lars Birkedal Cristiano Calcagno Alexandre David Fr´ed´eric Blanqui Manuel Campagnolo Anuj Dawar