Analysis and solution of different algorithmic problems

The goal of competitive programming is being able to find abstract solutions for some given algorithmic problems, and and also being able to code those ideas into an efficient and correct computer program. Performing this activity at a high level requires a bit of natural ability, (at least) hundreds of training hours, and a wide range of knowledge, obviously including many algorithms and data structures, some of them not trivial at all. This project constitutes a compilation of problems from several different relevant topics in competitive programming, with an explanation and analysis of their solution. Most of these problems were solved while training with the UPC programming teams, which have dominated their regional competition for more than one decade. The author hopes that this collection may eventually increase the interest of some readers towards competitive programming