AC自动机 专题

 // 求目标串中出现了几个模式串
 //====================
 #include <stdio.h>
 #include <algorithm>
 #include <iostream>
 #include <string.h>
 #include <queue>
 using namespace std;
 
 struct Trie
 {
     int next[][],fail[],end[];
     int root,L;
     int newnode()
     {
         for(int i = ;i < ;i++)
             next[L][i] = -;
         end[L++] = ;
         return L-;
     }
     void init()
     {
         L = ;
         root = newnode();
     }
     void insert(char buf[])
     {
         int len = strlen(buf);
         int now = root;
         for(int i = ;i < len;i++)
         {
             if(next[now][buf[i]-'a'] == -)
                 next[now][buf[i]-'a'] = newnode();
             now = next[now][buf[i]-'a'];
         }
         end[now]++;
     }
     void build()
     {
         queue<int>Q;
         fail[root] = root;
         for(int i = ;i < ;i++)
             if(next[root][i] == -)
                 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 = ;i < ;i++)
                 if(next[now][i] == -)
                     next[now][i] = next[fail[now]][i];
                 else
                 {
                     fail[next[now][i]]=next[fail[now]][i];
                     Q.push(next[now][i]);
                 }
         }
     }
     int query(char buf[])
     {
         int len = strlen(buf);
         int now = root;
         int res = ;
         for(int i = ;i < len;i++)
         {
             now = next[now][buf[i]-'a'];
             int temp = now;
             while( temp != root )
             {
                 res += end[temp];
                 end[temp] = ;
                 temp = fail[temp];
             }
         }
         return res;
     }
     void debug()
     {
         for(int i = ;i < L;i++)
         {
             printf("id = %3d,fail = %3d,end = %3d,chi = [",i,fail[i],end[i]);
             for(int j = ;j < ;j++)
                 printf("%2d",next[i][j]);
             printf("]\n");
         }
     }
 };
 char buf[];
 Trie ac;
 int main()
 {
     int T;
     int n;
     scanf("%d",&T);
     while( T-- )
     {
         scanf("%d",&n);
         ac.init();
         for(int i = ;i < n;i++)
         {
             scanf("%s",buf);
             ac.insert(buf);
         }
         ac.build();
         scanf("%s",buf);
         printf("%d\n",ac.query(buf));
     }
     return ;
 }

//输出每个模式串出现的次数
 
#include <iostream>
#include <stdio.h>
#include <string.h>
#include <algorithm>
#include <queue>
using namespace std;
 
char str[][];
struct Trie
{
    int next[*][],fail[*],end[*];
    int root,L;
    int newnode()
    {
        for(int i = ;i < ;i++)
            next[L][i] = -;
        end[L++] = -;
        return L-;
    }
    void init()
    {
        L = ;
        root = newnode();
    }
    void insert(char s[],int id)
    {
        int len = strlen(s);
        int now = root;
        for(int i = ;i < len;i++)
        {
            if(next[now][s[i]] == -)
                next[now][s[i]] = newnode();
            now = next[now][s[i]];
        }
        end[now] = id;
    }
    void build()
    {
        queue<int>Q;
        fail[root] = root;
        for(int i = ;i < ;i++)
            if(next[root][i] == -)
                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 = ;i < ;i++)
                if(next[now][i] == -)
                    next[now][i]=next[fail[now]][i];
                else
                {
                    fail[next[now][i]]=next[fail[now]][i];
                    Q.push(next[now][i]);
                }
        }
    }
    int num[];
    void query(char buf[],int n)
    {
        for(int i = ;i < n;i++)
            num[i] = ;
        int len=strlen(buf);
        int now=root;
        for(int i=;i<len;i++)
        {
            now=next[now][buf[i]];
            int temp = now;
            while( temp != root )
            {
                if(end[temp] != -)
                    num[end[temp]]++;
                temp = fail[temp];
            }
        }
        for(int i = ;i < n;i++)
            if(num[i] > )
                printf("%s: %d\n",str[i],num[i]);
    }
 
};
 
char buf[];
Trie ac;
void debug()
{
    for (int i = ; i < ac.L; i++)
    {
        printf("id = %3d ,fail = %3d ,end = %3d, chi = [",i,ac.fail[i],ac.end[i]);
        for (int j = ; j < ; j++)
            printf("%2d ",ac.next[i][j]);
        printf("]\n");
    }
}
int main()
{
//    freopen("in.txt","r",stdin);
//    freopen("out.txt","w",stdout);
    int n;
    while(scanf("%d",&n) == )
    {
        ac.init();
        for(int i = ;i < n;i++)
        {
            scanf("%s",str[i]);
            ac.insert(str[i],i);
        }
        ac.build();
        scanf("%s",buf);
        ac.query(buf,n);
    }
    return ;
}

转自bin神 orz