AC自动机(Aho-Corasick automation)模板 HDU：2222

 #include <iostream>
 #include <cstdio>
 #include <cstring>
 #include <queue>
 using namespace std;
 const int maxn = ;
 char S[];
 struct AC{
     int ch[maxn][],fail[maxn],end[maxn],root,cnt;
     void Init()
     {    memset(ch,,sizeof(ch));memset(fail,,sizeof(fail));
         memset(end,,sizeof(end));cnt=;root=;
     }
     void Insert(char *s)
     {    int len=strlen(s),node=root;
         for(int i=;i<len;i++)
         {    if(ch[node][s[i]-'`'])
                 node=ch[node][s[i]-'`'];
             else
                 node=ch[node][s[i]-'`']=++cnt;
         }
         end[node]++;
     }
     void Build()
     {
         queue<int>q;
         for(int i=;i<=;i++)
             if(ch[root][i])
                 fail[ch[root][i]]=root,q.push(ch[root][i]);
             else
                 ch[root][i]=root;
         while(!q.empty())
         {    int node=q.front();q.pop();
             for(int i=;i<=;i++)
             {    if(ch[node][i]){
                     fail[ch[node][i]]=ch[fail[node]][i];
                     q.push(ch[node][i]);
                 }
                 else
                     ch[node][i]=ch[fail[node]][i];
             }
         }
     }
     int Query(char *s)
     {    int len=strlen(s),node=root,ret=;
         for(int i=;i<len;i++)
         {    node=ch[node][s[i]-'`'];
             int temp=node;
             while(temp!=root)
                 ret+=end[temp],end[temp]=,temp=fail[temp];
         }
         return ret;
     }
 }A;
 int main()
 {
     int Q;
     scanf("%d",&Q);
     int n;
     while(Q--)
     {    scanf("%d",&n);
         A.Init();
         for(int i=;i<=n;i++)
         {    scanf("%s",S);
             A.Insert(S);
         }
         A.Build();
         scanf("%s",S);
         printf("%d\n",A.Query(S));
     }
     return ;
 }

题目来源：HDU2222