I had read a blog about solving matrix exponentiation without using matrices but just by using some iterative code(it was matrix expo in the background). It was written by some chinese purple(at that time) coder but I forgot to bookmark it so I lost it. Can somebody help me find it?
Not sure, maybe this one: An amazing way to calculate 10^18-th fibonacci number using 25 lines of code.
but he is Vietnamese :D