HDU 3065 病毒侵袭持续中 AC自动机

题意：找出模式串在文本串中出线的次数。

解题思路：裸AC自动机

解题代码：

// File Name: temp.cpp
// Author: darkdream
// Created Time: 2014年09月11日 星期四 15时18分26秒

#include<vector>
#include<list>
#include<map>
#include<set>
#include<deque>
#include<stack>
#include<bitset>
#include<algorithm>
#include<functional>
#include<numeric>
#include<utility>
#include<sstream>
#include<iostream>
#include<iomanip>
#include<cstdio>
#include<cmath>
#include<cstdlib>
#include<cstring>
#include<ctime>
#include<queue>
#define LL long long
#define maxn 1010*50
using namespace std;
int hs[1010];
struct Trie
{
    int next[maxn][26],fail[maxn],end[maxn];
    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 buf[],int K)
    {
        int len = strlen(buf);
        int now = root;
        for(int i = 0 ;i < len ;i ++)
        {
            int tt = buf[i] - 'A';
            if(next[now][tt] ==  -1)
            {
                next[now][tt] = newnode();
            }
            now = next[now][tt];
        }
        end[now] = K;
    }
    void build()
    {
        queue<int> Q;
        fail[root] = root; 
        for(int i = 0;i < 26;i ++)
        {
            if(next[root][i] == -1)
            {
                next[root][i] = root;  //指向root 是没有问题的，我们主要是通过end 数组对个数进行计数的。    
            }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]);
                }
            }
        }
    }
    void query(char buf[])
    {
        int now = root ; 
        int len = strlen(buf);
        for(int  i = 0 ;i <= len;i ++)
        {
            if(!(buf[i] <= 'Z' && buf[i] >= 'A'))
            {
                now = root ; 
                continue;
            }
            now = next[now][buf[i] - 'A'];
            int temp = now ; 
            while(temp != root)
            {
                if(end[temp])
                {
                    hs[end[temp]] ++ ; 
                }
                temp = fail[temp];
            }
        }
    }
};
char str[1005][100];
char buf[2100010];
Trie ac;
int main(){
    int n;
    while(scanf("%d",&n) != EOF)
    {
        ac.init();
        for(int i = 1 ;i <= n;i ++)
        {
            scanf("%s",str[i]);
            ac.insert(str[i],i);
        }
        ac.build();
        memset(hs,0,sizeof(hs));
        scanf("%s",buf);
        ac.query(buf);
        for(int i = 1;i <= n;i ++)
        {
            if(hs[i])
            {
                printf("%s: %d
",str[i],hs[i]);
            }
        }
    }
    return 0;
}