2015 多校联赛 ——HDU5384(AC自动机)

Sample Input
 
   
1 5 6 orz sto kirigiri danganronpa ooooo o kyouko dangan ronpa ooooo ooooo
 

Sample Output
 
   
1 1 0 3 7
 

题意:给n个母串,给m个匹配串,求每个母串依次和匹配串匹配,能得到的数目和

开始用KMP超时了,突然看见AC,把模板改一下就过了- -


#include
#include
#include
#include
using namespace std;
#define N 500010
char str[10010], keyword[10005];
char l[100005][10005];
int head, tail;

struct node
{
    node *fail;
    node *next[26];
    int count;
    node() //init
    {
        fail = NULL;
        count = 0;
        for(int i = 0; i < 26; ++i)
            next[i] = NULL;
    }
}*q[N];
node *root;

void insert(char *str) //建立Trie
{
    int temp, len;
    node *p = root;
    len = strlen(str);
    for(int i = 0; i < len; ++i)
    {
        temp = str[i] - 'a';
        if(p->next[temp] == NULL)
            p->next[temp] = new node();
        p = p->next[temp];
    }
    p->count++;
}

void build_ac() 
{
    q[tail++] = root;
    while(head != tail)
    {
        node *p = q[head++]; 
        node *temp = NULL;
        for(int i = 0; i < 26; ++i)
        {
            if(p->next[i] != NULL)
            {
                if(p == root) 
                    p->next[i]->fail = root;
                else
                {
                    temp = p->fail;
                    while(temp != NULL) 
                    {
                        if(temp->next[i] != NULL) 
                        {
                            p->next[i]->fail = temp->next[i];
                            break;
                        }
                        temp = temp->fail;
                    }
                    if(temp == NULL) 
                        p->next[i]->fail = root;
                }
                q[tail++] = p->next[i]; //入队
            }
        }
    }
}

int query() 
{
    int index, len, result;
    node *p = root; //Tire入口
    result = 0;
    len = strlen(str);
    for(int i = 0; i < len; ++i)
    {
        index = str[i] - 'a';
        while(p->next[index] == NULL && p != root) 
            p = p->fail;
        p = p->next[index];
        if(p == NULL)
            p = root;
        node *temp = p;
        while(temp != root && temp->count != -1)
        {
            result += temp->count;
            //temp->count = -1;
            temp = temp->fail;
        }
    }
    return result;
}

int main()
{
    int ncase, num,n;
    scanf("%d", &ncase);
    while(ncase--)
    {
        head= tail = 0;
        root = new node();
        scanf("%d%d", &n,&num);
        getchar();
        for(int i = 1;i <= n;i++)
            gets(l[i]);
        for(int i = 0; i < num; ++i)
        {
            gets(keyword);
            insert(keyword);
        }
        build_ac();
        for(int i = 1; i <= n; i++)
        {
            memccpy(str,l[i],0,sizeof(l[i]));
            //build_ac();
            printf("%d\n", query());
        }
    }
    return 0;
}








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