[模板]AC自动机

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e7 + 5;
const int MAX = 10000000;
int cnt;
struct node{
    node *next[26];
    node *fail;
    int sum;
};
node *root;
char key[70];
node *q[MAX];
int head,tail;
node *newnode;
char pattern[maxn];
int N;
void Insert(char s[])  //建trie树
{
    node *p = root;
    for(int i = 0; s[i]; i++)  //注意中间的东西，s[i]不为空时。
    {
        int x = s[i] - 'a';
        if(p->next[x] == NULL)
        {
            newnode = new node;  //先用newnode指针把地址建好，然后在31行直接传到p->next[x]
            for(int j=0;j<26;j++)
            newnode->next[j] = NULL;
            newnode->sum = 0;  //记录是几个单词的结尾
            newnode->fail = NULL;
            p->next[x] = newnode;
        }
        p = p->next[x];
    }
    p->sum++;
}
void build_fail_pointer()
{
    head = 0;
    tail = 1;
    q[head] = root;   //手动模拟队列
    node *p;
    node *temp;
    while(head < tail)
    {
        temp = q[head++];
        for(int i = 0; i <= 25; i++)
        {
            if(temp->next[i] != NULL)
            {
                if(temp == root)  //root的fail指针为自己
                {
                    temp->next[i]->fail = root;
                }
                else
                {
                    p = temp->fail;  //将父节点的fail传给儿子
                    while(p != NULL)
                    {
                        if(p->next[i] != NULL)
                        {
                            temp->next[i]->fail = p->next[i];
                            break;
                        }
                        p = p->fail;
                    }
                    if(p == NULL) temp->next[i]->fail = root;//如果失败，fail就为根节点
                }
                q[tail++] = temp->next[i];
            }
        }
    }
}
void ac_automation(char ch[])
{
    node *p = root;
    int len = strlen(ch);
    for(int i = 0; i < len; i++)  //主文本搜索到哪了
    {
        int x = ch[i] - 'a';
        while(p->next[x] == NULL&& p != root) p = p->fail;  //如果失败就从fail开始再找
        p = p->next[x];
        if(p == NULL) p = root; //判断是否找到了
        node *temp = p;
        while(temp != root)
        {
            if(temp->sum >= 0)  //如果没加过，就加
            {
               cnt += temp->sum;
               temp->sum = -1;
            }
            else break;  //加过就不加了
            temp = temp->fail;  //把相同后缀的单词都加上
        }
    }
}
int main()
{
    int T;
    scanf("%d",&T);
    while(T--)
    {
        root=new node;
        for(int j=0;j<26;j++) root->next[j] = NULL;
        root->fail = 0;
        root->sum = 0;
        scanf("%d",&N);
        getchar();
        for(int i = 1; i <= N; i++)
        {
            gets(key);
            Insert(key);
        }
        gets(pattern);
        cnt = 0;
        build_fail_pointer();
        ac_automation(pattern);
        printf("%d ",cnt);
    }
    return 0;
}

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<queue>
using namespace std;
#define duke(i,a,n) for(int i = a;i <= n;i++)
#define lv(i,a,n) for(int i = a;i >= n;i--)
#define clean(a) memset(a,0,sizeof(a))
const int INF = 1 << 30;
const int mod = 998244353;
typedef double db;
template <class T>
void read(T &x)
{
    char c;
    bool op = 0;
    while(c = getchar(), c < '0' || c > '9')
        if(c == '-') op = 1;
    x = c - '0';
    while(c = getchar(), c >= '0' && c <= '9')
        {x = x * 10 + c - '0';if(x > mod) x %= mod;}
    if(op) x = -x;
}
template <class T>
void write(T x)
{
    if(x < 0) putchar('-'), x = -x;
    if(x >= 10) write(x / 10);
    putchar('0' + x % 10);
}
const int maxn = 1e6 + 5;
char s[maxn];
int ch[maxn][30],cnt = 0,val[maxn],f[maxn],n;
int getnum(char c)
{
    return c - 'a';
}
void insert(char *s)
{
    int m = strlen(s);
    int now = 0;
    duke(i,0,m - 1)
    {
        int c = getnum(s[i]);
        if(!ch[now][c])
        ch[now][c] = ++cnt;
        now = ch[now][c];
    }
    val[now]++;
}
void build()
{
    queue <int> q;
    duke(i,0,25)
    {
        if(ch[0][i])
        q.push(ch[0][i]);
    }
    while(!q.empty())
    {
        int now = q.front();
        q.pop();
        duke(i,0,25)
        {
            if(ch[now][i])
            f[ch[now][i]] = ch[f[now]][i],q.push(ch[now][i]);
            else
            ch[now][i] = ch[f[now]][i];
        }
    }
}
int query(char *s)
{
    int len = strlen(s),now = 0,ans = 0;
    duke(i,0,len - 1)
    {
        int c = getnum(s[i]);
        now = ch[now][c];
        for(int j = now;j && val[j] != -1;j = f[j])
        ans += val[j],val[j] = -1;
    }
    return ans;
}
int main()
{
    read(n);
    duke(i,1,n)
    {
        scanf("%s",s);
        insert(s);
    }
    build();
    scanf("%s",s);
    printf("%d
",query(s));
    return 0;
}