poj 3461 Oulipo（kmp 模板题）

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;

char p[11111],t[1111111];

int fail[11111];

void get_fail()
{
int len = strlen(p);
fail[0] = -1;
int j = -1;
for(int i = 1;i<len;i++)
{
while(j >= 0 && p[i] != p[j+1]) j = fail[j];
if(p[i] == p[j+1]) j++;
fail[i] = j;
}
}

int kmp()
{
get_fail();
int len_p = strlen(p);
int len_t = strlen(t);
int cnt = 0;
int j = -1;
for(int i = 0;i<len_t;i++)
{
while(j >=0 && t[i] != p[j+1]) j = fail[j];
if(t[i] == p[j+1]) j++;
if(j == len_p - 1)
{
j = fail[j];
cnt++;
}
}
return cnt;
}

int main()
{
int _;
scanf("%d",&_);
while(_--)
{
scanf("%s%s",p,t);
printf("%d\n",kmp());
}
return 0;
}