HDU 2222 Keywords Search (AC自动机)

/*
Author: ACb0y
Date: 2011年12月29日21:59:25
Type: AC自动机
ProblemID: hdu 2222
*/
#include <iostream>
using namespace std;
struct node {
node * fail;
node * next[26];
int count;
};
node * queue[500005];
char keyword[55];
char str[1000005];
node * root;
node * get_node() {
node * p = (node *)malloc(sizeof(node));
p->count = 0;
p->fail = NULL;
memset(p->next, NULL, sizeof(p->next));
return p;
}
void insert(char * str) {
int len = strlen(str);
node * p_cur = root;
for (int i = 0; i < len; ++i) {
int pos = str[i] - 'a';
if (p_cur->next[pos] == NULL) {
p_cur->next[pos] = get_node();
}
p_cur = p_cur->next[pos];
}
p_cur->count++;
}
void build_fail() {
int front = 0;
int rear = 0;
root->fail = NULL;
queue[rear++] = root;
while (front < rear) {
node * p_cur = queue[front++];
node * temp = NULL;
for (int i = 0; i < 26; ++i) {
if (p_cur->next[i] != NULL) {
if (p_cur == root) {
p_cur->next[i]->fail = root;
} else {
temp = p_cur->fail;
while (temp != NULL) {
if (temp->next[i] != NULL) {
p_cur->next[i]->fail = temp->next[i];
break;
}
temp = temp->fail;
}
if (temp == NULL) {
p_cur->next[i]->fail = root;
}
}
queue[rear++] = p_cur->next[i];
}
}
}
}
int query() {
int cnt = 0;
int len = strlen(str);
node * p_cur = root;
for (int i = 0; i < len; ++i) {
int pos = str[i] - 'a';
while (p_cur->next[pos] == NULL && p_cur != root) {
p_cur = p_cur->fail;
}
p_cur = p_cur->next[pos];
if (p_cur == NULL) {
p_cur = root;
}
node * temp = p_cur;
while (temp != root && temp->count != -1) {
cnt += temp->count;
temp->count = -1;
temp = temp->fail;
}
}
return cnt;
}
void clear(node * root) {
node * p_cur = root;
for (int i = 0; i < 26; ++i) {
if (p_cur->next[i] != NULL) {
clear(p_cur->next[i]);
}
}
free(p_cur);
}
int main()
{
#ifndef ONLINE_JUDGE
freopen("in.txt", "r", stdin);
#endif
int cas;
scanf("%d", &cas);
while (cas--) {
int n;
root = get_node();
scanf("%d", &n);
for (int i = 0; i < n; ++i) {
scanf("%s", keyword);
insert(keyword);
}
build_fail();
scanf("%s", str);
printf("%d/n", query());
}
return 0;
}