AC自动机

来源：互联网发布：华泰软件工程有限公司编辑：程序博客网时间：2024/06/14 09:36

http://www.cnblogs.com/huangxincheng/archive/2012/12/02/2798317.html

http://www.cnblogs.com/Lyush/archive/2011/09/04/2165975.html

http://www.cnblogs.com/Booble/archive/2010/12/05/1897121.html

#include <queue>#include <stdio.h>#include <string.h>#include <algorithm>using namespace std;#define CLR(a,v) memset(a,v,sizeof(a))namespace Trie{    const int N = 1e6 + 5;    const int Size = 26;    int top;    struct Node{        Node *next[Size], *f;        int ended_cnt;    }node[N], *root;    inline Node* new_node()    {        node[top].ended_cnt = 0;        CLR(node[top].next,false);        return &node[top++];    }    void init()    {        top = 0;        root = new_node();    }    void insert(char *s)    {        Node *u = root;        for(int i=0;s[i];i++)        {            int id = s[i] - 'a';            if(u->next[id] == NULL)                u->next[id] = new_node();            u = u->next[id];        }        u->ended_cnt++;    }}namespace ACam{    using namespace Trie;    void get_fail()    {        queue<Node*> Q;        for(int i=0;i<Size;i++)        {            Node *&ch = root->next[i];            if(!ch)                ch = root;            else            {                ch->f = root;                Q.push(ch);            }        }        while(!Q.empty())        {            Node *cur = Q.front();Q.pop();            for(int i=0;i<Size;i++)            {                Node *&ch = cur->next[i];                if(!ch)                    ch = cur->f->next[i];                else                {                    ch->f = cur->f->next[i];                    Q.push(ch);                }            }        }    }    int match(char *s)    {        int ans = 0;        Node *u = root;        for(int i=0;s[i];i++)        {            int id = s[i] - 'a';            u = u->next[id];            Node *v = u;            while(v != root)            {                ans += v->ended_cnt;                v = v->f;            }        }        return ans;    }}