KMP算法

见csdn博主v_JULY_v的详解如下：
https://blog.csdn.net/v_JULY_v/article/details/7041827?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522166746739316800180687300%2522%252C%2522scm%2522%253A%252220140713.130102334..%2522%257D&request_id=166746739316800180687300&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2_alltop_positive~default-1-7041827-null-null.142^v62pc_new_rank,201^v3control,213^v1t3_esquery_v3&utm_term=kmp&spm=1018.2226.3001.4187