General

Name that anime move

So I just remembered about an anime movie that I didn't get to finish during a camping trip. I don't know what it was called though and this is where you come in! So there's pretty much this system kinda like facebook but it's used by everything and everyone. Like banking and even streetlights. One day a guy got a message for some "math riddle" and he was asked to solve the code. This code was the key to hacking this system. Then there's mass chaos with one guy taking over the cyber world which is connected to the real world. If anyone knows which anime movie this was please help me out? I really wanna finish it.

EDIT: The title was suppose to be "Name that anime movie"