Here are the refereed proceedings of the 6th Italian Conference on Algorithms and Computation, CIAC 2006. The 33 revised full papers presented together with 3 invited papers address such topics as sequential, parallel and distributed algorithms, data structures, approximation algorithms, randomized algorithms, on-line algorithms, graph algorithms, analysis of algorithms, algorithm engineering, algorithmic game theory, computational biology, computational complexity, communication networks, computational geometry, cryptography, discrete optimization, graph drawing, mathematical programming, and quantum algorithms.

This book constitutes the refereed proceedings of the 23rd Annual European Symposium on Algorithms, ESA 2015, held in Patras, Greece, in September 2015, as part of ALGO 2015. The 86 revised full papers presented together with two invited lectures were carefully reviewed and selected from 320 initial submissions: 71 out of 261 in Track A, Design and Analysis, and 15 out of 59 in Track B, Engineering and Applications. The papers present real-world applications, engineering, and experimental analysis of algorithms.