The papers in this volume were selected for presentation at the 6th Annual International Computing and Combinatorics Conference (COCOON2000), in Sydney, Australia from July 26 - 28, 2000. The topics cover many areas in t- oretical computer science and combinatorial optimization. There were 81 high quality papers submitted to COCOON2000. Each paper was reviewed by at least three program committee members, and the 44 papers were selected. It is expected that most of them will appear in a more complete form in scientic journals. In addition to the selected papers, the volume also contains the papers from two invited keynote speeches by Christos Papad- itriou and Richard Brent. This year the Hao Wang Award was given to honor the paper judged by the programcommittee to have the greatest merit. The recipient is Approximating Uniform TriangularMeshes in Polygons"byFranz Aurenhammer, NaokiKatoh, Hiromichi Kojima, Makoto Ohsaki, and Yinfeng Xu. The rst Best Young - searcher paper award was given to William Duckworth for his paper Maximum Induced Matchings of Random Cubic Graphs". We wish to thank all who have made this meeting possible: the authors for submitting papers, the program committee members and the external referees, sponsors, the local organizers, ACM SIGACT for handling electronic subm- sions,Springer-Verlagfor their support, and Debbie Hatherellfor her assistance.

Includes supplementary material: sn.pub/extras

Invited Talks.- Theoretical Problems Related to the Internet.- Recent Progress and Prospects for Integer Factorisation Algorithms.- Hao Wang Award Paper.- Approximating Uniform Triangular Meshes in Polygons.- The Best Young Researcher Paper.- Maximum Induced Matchings of Random Cubic Graphs.- Computational Geometry 1.- A Duality between Small-Face Problems in Arrangements of Lines and Heilbronn-Type Problems.- On Local Transformation of Polygons with Visibility Properties.- Graph Drawing.- Embedding Problems for Paths with Direction Constrained Edges.- Characterization of Level Non-planar Graphs by Minimal Patterns.- Rectangular Drawings of Plane Graphs Without Designated Corners.- Computing Optimal Embeddings for Planar Graphs.- Graph Theory and Algorithms 1.- Approximation Algorithms for Independent Sets in Map Graphs.- Hierarchical Topological Inference on Planar Disc Maps.- Efficient Algorithms for the Minimum Connected Domination on Trapezoid Graphs.- Complexity, Discrete Mathematics, and Number Theory.- Parameterized Complexity of Finding Subgraphs with Hereditary Properties.- Some Results on Tries with Adaptive Branching.- Optimal Coding with One Asymmetric Error: Below the Sphere Packing Bound.- Closure Properties of Real Number Classes under Limits and Computable Operators.- Graph Theory and Algorithms 2.- A Characterization of Graphs with Vertex Cover Six.- On the Monotonicity of Minimum Diameter with Respect to Order and Maximum Out-Degree.- Online Algorithms.- Online Independent Sets.- Two-Dimensional On-Line Bin Packing Problem with Rotatable Items.- Better Bounds on the Accommodating Ratio for the Seat Reservation Problem.- Ordinal On-Line Scheduling on Two Uniform Machines.- Parallel and Distributed Computing.- Agents, Distributed Algorithms, and Stabilization.- A Fast Sorting Algorithm and Its Generalization on Broadcast Communications.- Efficient List Ranking Algorithms on Reconfigurable Mesh.- Computational Geometry 2.- Tripods Do Not Pack Densely.- An Efficient k Nearest Neighbor Searching Algorithm for a Query Line.- Tetrahedralization of Two Nested Convex Polyhedra.- Efficient Algorithms for Two-Center Problems for a Convex Polygon.- Combinatorial Optimization.- On Computation of Arbitrage for Markets with Friction.- On Some Optimization Problems in Obnoxious Facility Location.- Generating Necklaces and Strings with Forbidden Substrings.- Optimal Labelling of Point Features in the Slider Model.- Data Structures and Computational Biology.- Mappings for Conflict-Free Access of Paths in Elementary Data Structures.- Theory of Trinomial Heaps.- Polyhedral Aspects of the Consecutive Ones Problem.- The Complexity of Physical Mapping with Strict Chimerism.- Learning and Cryptography.- Logical Analysis of Data with Decomposable Structures.- Learning from Approximate Data.- A Combinatorial Approach to Asymmetric Traitor Tracing.- Removing Complexity Assumptions from Concurrent Zero-Knowledge Proofs.- Automata and Quantum Computing.- One-Way Probabilistic Reversible and Quantum One-Counter Automata.- Similarity Enrichment in Image Compression through Weighted Finite Automata.- On the Power of Input-Synchronized Alternating Finite Automata.- Ordered Quantum Branching Programs Are More Powerful than Ordered Probabilistic Branching Programs under a Bounded-Width Restriction.