poj 3461 KMP算法的应用

//============================================================================
//
// >     File        :    poj2406.cpp
// >     Author      :    flowertree
// >     Time        :    2015年12月15日
// >     Algorithm   :    KMPnext数组的应用
//
//============================================================================

#include <iostream>
#include <string.h>
#include <stdio.h>
#include <algorithm>
using namespace std;

#define MAX 1000005
#define MAX_sub 10005

char str[MAX];
char str_sub[MAX_sub];
int Next[MAX_sub];

void getnext(int len)
{
	int i = 0;
	int j = -1;
	Next[0] = -1;
	while(i < len)
	{
		if(j == -1 || str_sub[i] == str_sub[j])
		{
			++i;
			++j;
			if(i == len)
			{
				Next[i] = j;
				return ;
			}
			if(str_sub[i] != str_sub[j])
				Next[i] = j;
			else
				Next[i] = Next[j];
		}
		else
			j = Next[j];
	}
}

int KMP(int len, int len_sub)
{
	int num = 0;
	int i = 0;
	int j = 0;
	while(i < len)
	{
		if(j == -1 || str[i] == str_sub[j])
		{
			++i;
			++j;
			if(j == len_sub)
			{
				num++;
				j = Next[len_sub];
			}
		}
		else
			j = Next[j];
	}
	return num;
}

int main()
{
	int m;
	cin >> m;
	while(m--)
	{
		scanf("%s", str_sub);
		scanf("%s", str);
		int len_sub = strlen(str_sub);
		int len = strlen(str);
		getnext(len_sub);
		int temp = KMP(len, len_sub);
		cout << temp << endl;
	}
	system("pause");
	return 0;
}