Computations Modulo P in Competitive Programming

Tutorial for beginners on computations modulo P in competitive programming. In so many Codeforces problems, we need to print the answer modulo M, most often M=10^9+7. What's the reason for that and how should it affect your code? Why modular subtraction is tricky and division even more difficult (modular inverse uses this https://en.wikipedia.org/wiki/Euler%27s_theorem)? Watch the video, then solve introductory problems here https://cses.fi/problemset/ and read Competitive Programmer's Handbook for some structured knowledge https://cses.fi/book/book.pdf Subscribe for more educational videos on algorithms, coding interviews and competitive programming. - Github repository: https://github.com/Errichto/youtube - Live streams on 2nd YT channel and on Twitch: https://www.youtube.com/errichto2 & https://www.twitch.tv/errichto - FB and Twitter: https://www.facebook.com/errichto & https://twitter.com/errichto - Frequently Asked Questions: https://github.com/Errichto/youtube/wiki/FAQ #Coding #Programming