Hi, I am a high school student trying to improve in order to compete in the IOI. Yesterday, after 4 months of practice, I have become a specialist on codeforces. Now that I have somewhat got used to how I should practice constructive and greedy algorithms, I have a question for you. What topics should I focus on studying next? By topics I mean stuff like graphs,dp (etc.). Please assist me with your knowledge. Thank you in advance.