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hdu2222 字符串多模匹配算法 采用kuangbin模板

#include <stdio.h>

#include <algorithm>

#include <iostream>

#include <string.h>

#include <queue>

using namespace std;

struct Trie

{

    int next[500010][26],fail[500010],end[500010];

    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;

                temp = fail[temp];

            }

        }

        return res;

    }

    void debug()

    {

        for(int i = 0;i < L;i++)

        {

            printf("id = %3d,fail = %3d,end = %3d,chi = [",i,fail[i],end[i]);

            for(int j = 0;j < 26;j++)

                printf("%2d",next[i][j]);

            printf("]\n");

        }

    }

};

char buf[1000010];

Trie ac;

int main()

{

    int T;

    int n;

    scanf("%d",&T);

    while( T-- )

    {

        scanf("%d",&n);

        ac.init();

        for(int i = 0;i < n;i++)

        {

            scanf("%s",buf);

            ac.insert(buf);

        }

        ac.build();

        scanf("%s",buf);

        printf("%d\n",ac.query(buf));

    }

    return 0;

}

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