This is coming from my suggestion above, but in my suggestion, I omitted "but extremely difficult for computers to solve", leaving it with: > P problems are ea

This is coming from my suggestion above, but in my suggestion, I omitted "but extremely difficult for computers to solve", leaving it with: > P problems are easy for computers to solve, and NP problems are easy for computers to check answers for. The problem is the text still uses "NP problems" and "NP complete problems" interchangeably, when it shouldn't. (The diagram at the top gets it right!)