KMP + POJ3461

模板：

void get_next(){
	int pLen = strlen(p);
	nxt[0] = -1;
	int k = -1;
	int j = 0;
	while (j < pLen - 1){
		if(k == -1 || p[j] == p[k]){
			++k;
			++j;
			nxt[j] = k;
		}
		else{
			k = nxt[k];
		}
	}
}
int kmp(){
	int i = 0;
	int j = 0;
	int sLen = strlen(s);
	int pLen = strlen(p);
	while (i < sLen && j < pLen){
		if(j == -1 || s[i] == p[j]){
			i++;
			j++;
		}
		else{
			j = nxt[j];
		}
	}
	if (j == pLen)	return i - j;
	else return -1;
}

POJ 3461

      看样例应该知道题意了叭QAQ 

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstring>
#include<string>

using namespace std;
const int maxn = 1e6 + 5;

char T[10005];
char S[maxn];
int nxt[10005];
int S_len,T_len,ans,t;

void get_nxt(){
	nxt[0] = -1;
	int k = -1;
	int j = 0;
	while(j < T_len - 1){
		if(k == -1 || T[j] == T[k]){
			++k;
			++j;
			nxt[j] = k;
		}
		else k = nxt[k];
	}
}

int kmp(){
	int i = 0;
	int j = 0;
	while(i < S_len){
		if(j == -1 || S[i] == T[j]){
			i++;
			j++;
		}
		else j = nxt[j];
		if(j == T_len){
			ans++;
			i --;
			j = nxt[j - 1];
		}
	}
	return ans;
}

int main()
{
	scanf("%d",&t);
	while(t--){
		ans = 0;
		scanf("%s",T);
		scanf("%s",S);
		S_len = strlen(S);
		T_len = strlen(T);
		get_nxt();
		ans = kmp();
		cout << ans << endl;
	}
}