AC自动机-HDU2222-模板题

http://acm.hdu.edu.cn/showproblem.php?pid=2222

一个AC自动机的模板题。用的kuangbin的模板，静态建Trie树。可能遇到MLE的情况要转动态建树。

AC自动机的讲解看这里

http://blog.csdn.net/niushuai666/article/details/7002823

http://blog.csdn.net/mobius_strip/article/details/22549517

/*--------------------------------------------------------------------------------------*/
//        Helica's header 
//        Second Editions
//        2015.11.7
//
#include <algorithm>
#include <iostream>
#include <cstring>
#include <ctype.h>
#include <cstdlib>
#include <cstdio>
#include <vector>
#include <string>
#include <queue>
#include <stack>
#include <cmath>
#include <set>
#include <map>//debug function for a N*M array 
#define debug_map(N,M,G) printf("\n");for(int i=0;i<(N);i++)\
{for(int j=0;j<(M);j++){\
printf("%d",G[i][j]);}printf("\n");}                
//debug function for int,float,double,etc.
#define debug_var(X) cout<<#X"="<<X<<endl;
/*--------------------------------------------------------------------------------------*/
using namespace std;int N,M,T;struct Trie
{int next[500010][26],fail[500010],end[500010];int root,L;int newnode(){for(int i=0;i<26;i++) next[L][i] = -1;end[L++] = 0;return L-1;}void init(){L = 0;root = newnode();}void insert(char *s){int len = strlen(s);int now = root;for(int i=0;i<len;i++){if(next[now][s[i]-'a'] == -1)next[now][s[i]-'a'] = newnode();now = next[now][s[i]-'a'];}end[now]++;}void build(){queue <int> Q;fail[root] = root;for(int i=0;i<26;i++)if(next[root][i] == -1)next[root][i] = root;else{fail[next[root][i]] = root;Q.push(next[root][i]);}while(!Q.empty()){int now = Q.front();Q.pop();for(int i=0;i<26;i++){if(next[now][i] == -1)next[now][i] = next[fail[now]][i];else{fail[next[now][i]] = next[fail[now]][i];Q.push(next[now][i]);}}}}int query(char *s){int len = strlen(s);int now = root;int ans = 0;for(int i=0;i<len;i++){now = next[now][s[i]-'a'];int temp = now;while(temp != root){ans += end[temp];end[temp] = 0;temp = fail[temp];}}return ans;}void debug(){for(int i=0;i<L;i++){printf("id = %3d,fail = %3d,end = %3d,chi = [",i,fail[i],end[i]);for(int j=0;j<26;j++)printf("%2d",next[i][j]);printf("]\n");}}
};char buf[1000100];
Trie ac;int main()
{scanf("%d",&T);while(T--){ac.init();scanf("%d",&N);for(int i=0;i<N;i++){scanf("%s",buf);ac.insert(buf);}ac.build();//ac.debug();scanf("%s",buf);printf("%d\n",ac.query(buf));}
}