Introduction - If you have any usage issues, please Google them yourself
Series of simple pattern matching algorithm is O (N ^ 2), and can make use of KMP (from DEKnuth, JHMorris, VRPratt made) algorithm to improve the algorithm to linear. KMP algorithm and simple algorithm is different: the " mismatch" situation. pointer completely different to back, KMP algorithm first part of the basis of information match, the pointer will skip the match do not have to match the position.