hdu5384(AC自動機)

這道題是多模字符串匹配的題，需要用到AC自動機。直接套模板AC。

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <queue>

using namespace std;
struct Trie
{
    int next[100002][26],fail[100002],end[100002];
    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 len = strlen(buf);
        int now = root;
        for(int i = 0; i < len; i++)
        {
            if(next[now][buf[i]-'a'] == -1)
                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 = 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 buf[])
    {
        int len = strlen(buf);
        int now = root;
        int res = 0;
        for(int i = 0; i < len; i++)
        {
            now = next[now][buf[i]-'a'];
            int temp = now;
            while( temp != root )
            {
                res += end[temp];
                //end[temp] = 0;    //爲了避免重複計數而做的，這裏不需要。
                temp = fail[temp];
            }
        }
        return res;
    }
};

char buf[10001];
Trie ac;
int m;
char s[100001][10002];
int main()
{
    int T;
    int n;
    scanf("%d",&T);
    while( T-- )
    {
        scanf("%d%d",&n, &m);
        ac.init();
        for(int i = 0; i < n; i++)
        {
            scanf(" %s", s[i]);
        }
        for(int i = 0; i < m; i++)
        {
            scanf("%s",buf);
            ac.insert(buf);
        }
        ac.build();
        for(int i = 0; i < n; i++)
        {
            printf("%d\n",ac.query(s[i]));
        }
    }
    return 0;
}