How LGM like tourist, Um_Nik, Petr, dotorya, ACRUSH , rng58 etc. are able to come up with such complex ideas which are required to solve div 1 e or atcoder grand contest last 2 problems which are almost unsolvable. From where they learn these hard tricks,methods and maths(imo level). Like tourist submits first 3 problems of div1 within 10 minutes.

Moreover, if you see problems from google code jam finals, distributed code jam they required very deep observation and intution, How they reach the correct observation and solution everytime.