Robert Geretschläger, Józef Kalinowski, Jaroslav Švrček, "A Central European Olympiad: The Mathematical Duel" 2018 | ISBN-10: 9813226161, 9813223901 | 292 pages | PDF | 7 MB
Programming Challenges: The Programming Contest Training Manual by Steven S. Skiena, Miguel A. Revilla English | PDF | 2003 | 375 Pages | ISBN : 0387001638 | 2.2 MB
Studying the challenges of problems from international programming competitions is an effective way to improve your algorithmic and coding skills and understanding.