KMP算法

算法模板

//Author LJH

//www.cnblogs.com/tenlee

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <cctype>

#include <cmath>

#include <algorithm>

#include <vector>

#include <queue>

#include <map>

#define clc(a, b) memset(a, b, sizeof(a))

using namespace std;



const int inf = 0x3f;

const int INF = 0x3f3f3f3f;

const int maxn = 5e6+5;



char par[maxn], son[maxn];

int next[maxn];



void get_next()

{

    int len = strlen(son);

    next[0] = next[1] = 0; 

    for(int i = 1; i < len; i++)

    {

        int j = next[i];

        while(j && son[i] != son[j]) j = next[j];

        next[i+1] = son[i] == son[j] ? j+1 : 0;

    }

}

void kmp()

{

    get_next();



    int nu = 0;

    int nlen = strlen(par), mlen = strlen(son);

    int i = 0, j = 0;

    for(i = 0; par[i]; i++)

    {

        while(j && par[i] != son[j])

        {

            j = next[j];

        }

        if(par[i] == son[j]) 

        {

            j++;

        }

        if(j == mlen)

        {

            printf("case %d#  %d\n", ++nu, i - mlen + 1);

            j = 0;

        }

    }

}



int main()

{

    while(true)

    {

        gets(son);

        gets(par);

        kmp();

    }

    return 0;

}