Fun with Algorithms [electronic resource] : 4th International Conference, FUN 2007, Castiglioncello, Italy, June 3-5, 2007. Proceedings / edited by Pierluigi Crescenzi, Giuseppe Prencipe, Geppino Pucci.

On Embedding a Graph in the Grid with the Maximum Number of Bends and Other Bad Features -- Close Encounters with a Black Hole or Explorations and Gatherings in Dangerous Graphs -- Fun with Sub-linear Time Algorithms -- Wooden Geometric Puzzles: Design and Hardness Proofs -- HIROIMONO Is NP-Complete -- Tablatures for Stringed Instruments and Generating Functions -- Knitting for Fun: A Recursive Sweater -- Pictures from Mongolia – Partial Sorting in a Partial World -- Efficient Algorithms for the Spoonerism Problem -- High Spies (or How to Win a Programming Contest) -- Robots and Demons (The Code of the Origins) -- The Traveling Beams Optical Solutions for Bounded NP-Complete Problems -- The Worst Page-Replacement Policy -- Die Another Day -- Approximating Rational Numbers by Fractions -- Cryptographic and Physical Zero-Knowledge Proof Systems for Solutions of Sudoku Puzzles -- Sorting the Slow Way: An Analysis of Perversely Awful Randomized Sorting Algorithms -- The Troubles of Interior Design–A Complexity Analysis of the Game Heyawake -- Drawing Borders Efficiently -- The Ferry Cover Problem -- Web Marshals Fighting Curly Link Farms -- Intruder Capture in Sierpi?ski Graphs -- On the Complexity of the Traffic Grooming Problem in Optical Networks.

ThisvolumecontainsthepaperspresentedattheFourthInternationalConf- enceonFunwithAlgorithms(FUN2007),heldJune3–5,2007inthebeautiful TuscaniancoastaltownofCastiglioncello,Italy. FUN is a three-yearly conference dedicated to the use, design, and ana- sisofalgorithmsanddatastructures,focusingonresultsthatprovideamusing, witty but nonetheless originaland scienti?cally profound contributions to the area. ThepreviousthreemeetingswereheldonElbaIsland,Italy,andspecial issuesofthejournals Theoretical Computer Science (FUN1998), Discrete - plied Mathematics(FUN2001),andTheory of Computing Systems(FUN2004) featureextendedversionsofselectedpapersfromthethreeconferenceprograms. InresponsetotheCallforPapersforFUN2007,wereceived41submissions from 25 countries. Each submission was reviewed by at least three Program Committeemembers. Attheendoftheselectionprocess,thecommitteedecided toaccept20papers. TheprogramalsoincludesthreeinvitedtalksbyGiuseppe Di Battista (U. Rome III, Italy), Nicola Santoro (Carleton U. , Canada), and LucaTrevisan(U. C. Berkeley,USA). WewishtothankalltheauthorswhosubmittedtheirpaperstoFUN2007 andthuscontributedtothecreationofahigh-qualityprogramandentertaining meeting,aswellasthecolleagueswhoacceptedtoserveontheProgramC- mitteeandprovidedinvaluablehelpwiththereviewingprocess. Wealsowishto thanktheexternalreviewers(listedonthefollowingpages)includingthosewho completedurgentreviewsduringthediscussionphase. Papersubmission,sel- tion,andgenerationoftheproceedingswasgreatlyeasedbytheuseofthepubl- domainEasyChair ConferenceSystem(http://www. easychair. org). Wewish tothanktheEasyChaircreatorsandmaintainersfortheirsel?esscommittment tothescienti?ccommunity. Finally,specialthanksgotoVincenzoGervasi,whose constanthelpanddedicationwascrucialinmakingFUN2007asuccessfulevent. April2007 PierluigiCrescenzi GiuseppePrencipe GeppinoPucci Conference Organization Program Chairs PierluigiCrescenzi(UniversityofFirenze,Italy) GeppinoPucci(UniversityofPadua,Italy) Program Committee NancyAmato(TexasA&MUniversity,USA) NinaAmenta(UniversityofCaliforniaatDavis,USA) MarcellaAnselmo(UniversityofSalerno,Italy) AnnaBernasconi(UniversityofPisa,Italy) PaoloBoldi(UniversityofMilano,Italy) IreneFinocchi(UniversityofRoma”LaSapienza”,Italy) LuisaGargano(UniversityofSalerno,Italy) SandyIrani(UniversityofCaliforniaatIrvine,USA) ChristosKaklamanis(UniversityofPatras,Greece) ShayKutten(Technion,Haifa,Israel) FabrizioLuccio(UniversityofPisa,Italy) BernardMans(MacquarieUniversity,Australia) PaoloPenna(UniversityofSalerno,Italy) AndreaRicha(ArizonaStateUniversity,Tempe,USA) IainStewart(UniversityofDurham,UK) ErkkiSutinen(UniversityofJoensuu,Finland) DenisTrystram(ID-IMAGGrenoble,France) PeterWidmayer(ETHZurich,Switzerland) Local Organization VincenzoGervasi(UniversityofPisa,Italy) GiuseppePrencipe(UniversityofPisa,Italy) External Reviewers LucaBecchetti HajoBroersma ValentinaCiriani DavidCoudert StefanDantchev AnnalisaDeBonis GianlucaDeMarco VIII Organization MiriamDiIanni PaolaFlocchini TomFriedetzky GiuliaGalbiati GoranKonjevod ZviLotker OrnellaMenchi FilippoMignosi ManalMohammed MelihOnus LindaPagli FannyPascual AndreaPietracaprina SrinivasaRao AdeleRescigno AndreaRicha GianlucaRossi MassimoSantini ErikSaule MarinellaSciortino RiccardoSilvestri CorinneTouati DenisTrystram SebastianoVigna IvanVisconti DonglinXia MicheleZito RosalbaZizza Table of Contents On Embedding a Graph in the Grid with the Maximum Number of Bends and Other Bad Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 GiuseppeDiBattista,FabrizioFrati,andMaurizioPatrignani Close Encounters With a Black Hole or Explorations and Gatherings in Dangerous Graphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 NicolaSantoro Fun with Sub-linear Time Algorithms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 LucaTrevisan Wooden Geometric Puzzles: Design and Hardness Proofs. . . . . . . . . . . . . . 16 HelmutAlt,HansBodlaender,MarcvanKreveld,Gu ¨nterRote,and GerardTel HIROIMONO Is NP-Complete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 DanielAndersson Tablatures for Stringed Instruments and Generating Functions. . . . . . . . . 40 DavideBaccherini,DonatellaMerlini,andRenzoSprugnoli Knitting for Fun: A Recursive Sweater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .