KMP算法
/* * main.cpp * * Created on: 2016年8月29日 * Author: godsome */ #include <iostream> #include <cstdio> #include <cstring> using namespace std; int next[100]; int Index_KMP(char s[], char t[]){ int len_s = strlen(s), len_t = strlen(t); int i = 0, j = 0; while(i < len_s && j < len_t){ if(s[i] == t[j]){ i++; j++; } else if(j == 0) i++; else j = next[j-1] + 1; } if(j == len_t) return i - len_t; else return -1; } void get_next(char str[], int next[]){ int len = strlen(str); int i, j; next[0] = -1; for(i = 1; i < len; i++){ j = next[i-1]; while(str[j+1]!=str[i] && j>=0) j = next[j]; if(str[i] == str[j+1]) next[i] = j + 1; else next[i] = -1; } } int main(){ char *p = "ababcabcacbab"; char *t = "abcac"; get_next(t, next); int pos = Index_KMP(p, t); printf("%d\n", pos); return 0; }