This book constitutes the refereed proceedings of the 4th International Conference on Fun with Algorithms, FUN 2007, held in Castiglioncello, Italy in June 2007. It details the use, design, and analysis of algorithms and data structures, focusing on results that provide amusing, witty, but nonetheless original and scientifically profound, contributions to the area.

The papers in this volume were presented at the Second Italian Conference onAlgorithms and Complexity, held in February 1994 in Rome. This biannual conference series is intended to present research contributions in theory and applications of sequential, parallel, and distributed algorithms, data structures, and computational complexity. The volume contains four invited presentations and 14 regular presentations selected from 32 submissions, each of which was evaluated by at least four program committee members. The invited presentations are by J. Hartmanis and S. Chari, A. Garg and R. Tamassia, S.C. Sahinalp and U. Vishkin, and M. Yannakakis.

This book is an up-to-date documentation of the state of the art in combinatorial optimization, presenting approximate solutions of virtually all relevant classes of NP-hard optimization problems. The well-structured wealth of problems, algorithms, results, and techniques introduced systematically will make the book an indispensible source of reference for professionals. The smooth integration of numerous illustrations, examples, and exercises make this monograph an ideal textbook.