←all notes Competitive Programming resources 2021-11-01, U: 2022-04-22 Platforms Old OI contests Contests Algorithm libraries Tools Books In English In Lithuanian Platforms CodeForces HackerRank CodeChef USACO Yosupo SPOJ Old OI contests CSES.FI (BOI, CEOI) Yandex (IOI) Checklist for OI Problems Contests Code Jam HashCode Algorithm libraries CP Algorithms Geeks for Geeks Tools Graph editor Geogebra Books In English Competitive Programmer's Handbook Competitive Programming Looking for a challenge In Lithuanian NMA knyga