Matrix Exponentiation + Fibonacci in log(N)

Codeforces training contest: https://codeforces.com/gym/102644 This is a tutorial on matrix exponentiation, a tool that allows you to quickly find the n-th Fibonacci number or quickly compute the number of very long paths in a graph. After watching the video, try to solve the first 6 problems in the CF training contest. I will soon post another video (or make a live stream?) with solutions to those problems, and the last 3 hard problems. 0:00 Introduction & Prerequisites 1:13 A. Random Mood 6:17 B. String Mood 15:12 Implementation 19:38 General Recipe 23:17 C. Fibonacci 26:30 C++ Recipe 27:56 Random Again 28:27 Complexity & Summary 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:    / errichto2   &   / errichto   FB and Twitter:   / errichto   &   / errichto   Frequently Asked Questions: https://github.com/Errichto/youtube/w... #Coding #Programming