hdu 2222 Keywords Search

#include <cstring>
#include <cstdio>
#define N 500010
struct node
{
    int cnt;
    node * next[27],* fail;
}*Q[N],*root;
int T;
node * create()
{
    node * rt=new node;
    rt->cnt=0;
    rt->fail=0;
    memset(rt->next,0,sizeof(rt->next));
    return rt;
}
void ins(char *a)
{
    node * p=root;
    char *q=a;
    while(*q)
    {
        int id=*q-‘a‘+1;
        if(p->next[id]==NULL) p->next[id]=create();
        p=p->next[id];
        q++;
    }
    p->cnt++;
}
void build()
{
    int head=0,tail=1;
    Q[tail]=root;
    while(head!=tail)
    {
        node * now=Q[++head];
        node * tmp=NULL;
        for(int i=1;i<=26;i++)
        {
            if(now->next[i]!=NULL)
            {
                if(now==root) now->next[i]->fail=root;
                else
                {
                    tmp=now->fail;
                    while(tmp!=NULL)
                    {
                        if(tmp->next[i]!=NULL)
                        {
                            now->next[i]->fail=tmp->next[i];
                            break;
                        }
                        tmp=tmp->fail;
                    }
                    if(tmp==NULL)
                        now->next[i]->fail=root;
                }
                Q[++tail]=now->next[i];
            }
        }
    }
}
int query(char *a)
{
    int ret=0;
    char *q=a;
    node *p=root;
    while(*q)
    {
        int id=*q-‘a‘+1;
        while(p->next[id]==NULL&&p!=root) p=p->fail;
        p=p->next[id];
        if(p==NULL) p=root;
        node *tmp=p;
        while(tmp!=root&&tmp->cnt!=-1)
        {
            ret+=tmp->cnt;
            tmp->cnt=-1;
            tmp=tmp->fail;
        }
        ++q;
    }
    return ret;
}
int main()
{
    scanf("%d",&T);
    for(int n;T--;)
    {
        root=create();
        char str[55];
        scanf("%d",&n);
        for(;n--;)
        {
            scanf("%s",str);
            ins(str);
        }
        build();
        char key[1000005];
        scanf("%s",key);
        printf("%d\n",query(key));
    }
    return 0;
}