kmp算法

#include<iostream>
using namespace std;
#include<string>

void nextFun(char* str, int* next) {
    next[0] = 0;
    int k = 0;
    int len = strlen(str);
    for (int i = 1; i < len; i++) {
        while (k > 0 && str[k] != str[i])
            k = next[k - 1];
        if (str[i] == str[k]) {
            k++;
        }
        next[i] = k;
    }
}

int KMP(char* str, char* pattern, int* next) {
    int res = 0;
    int len = strlen(str), lenPat = strlen(pattern);
    int k = 0;
    for (int i = 0; i < len; i++) {
        while (k > 0 && str[i] != pattern[k])
            k = next[k - 1];
        if (str[i] == pattern[k])
            k++;
        if (k == lenPat) {
            res++;
            cout << "the matching pattern is shifting "<<i-lenPat+1<<endl;
            k = next[k-1];
        }
    }
    return res;
}