AC自动机模板

最近看了下AC自动机，觉得没有什么卵用。不过还是记录下。

#define MAXTREENODE 400400

struct ACtree
{
    int next[MAXTREENODE][26],times[MAXTREENODE],fail[MAXTREENODE];
    int head,treeid;
    int que[MAXTREENODE];
    int qf,qd;
    int newnode()
    {
        memset(next[treeid],-1,sizeof(next[treeid]));
        times[treeid]=0;
        fail[treeid]=-1;
        treeid++;
        return treeid-1;
    }

    void init()
    {
        treeid=0;
        head = newnode();
    }

    void acinsert(char *str)
    {
        int len=strlen(str);
        int tmpid=head;
        for(int i=0;i<len;i++)
        {
            int to=str[i]-'a';
            if(next[tmpid][to]==-1) next[tmpid][to] = newnode();
            tmpid = next[tmpid][to];
        }
        times[ tmpid ] ++;
    }

    void build()
    {
        qf=qd=0;
        for(int i=0;i<26;i++)
            if(next[head][i] == -1) next[head][i] = head;
            else
            {
                que[qf++] = next[head][i];
                fail[ next[head][i] ] = head;
            }
        while( qf>qd )
        {
            int cur = que[qd++];
            for(int i=0;i<26;i++)
            {
                if( next[cur][i] == -1 ) next[cur][i] = next[ fail[cur] ][i];
                else
                {
                    que[qf++] = next[cur][i];
                    fail[ next[cur][i] ] = next[ fail[cur] ][i];
                }
            }
        }
    }
    int acquery(char * str)
    {
        int len=strlen(str);
        int acsum=0;
        int nowid=head;
        for(int i=0;i<len;i++)
        {
            int to=str[i]-'a';
            nowid = next[nowid][to];
            int tmpid=nowid;
            while(tmpid!=head)
            {
                acsum += times[tmpid];
                times[ tmpid ] = 0;
                tmpid = fail[tmpid];
            }
        }
        return acsum;
    }
};