AC自动机

存个板子

#include <bits/stdc++.h>
using namespace std;

const int maxn = 1e6 + 10;
int trie[maxn][26]; 
int flag[maxn];
int fail[maxn];  
int tol;

void Insert(char *s) {
    int root = 0;
    int len = strlen(s);
    for (int i = 0; i < len; i++) {
        int id = s[i] - 'a';
        if (!trie[root][id]) trie[root][id] = ++tol;
        root = trie[root][id];
    }
    flag[root]++;
}

void getfail() {
    queue<int> que;
    for (int i = 0; i < 26; i++) {
        if (trie[0][i]) {
            que.push(trie[0][i]);
            fail[trie[0][i]] = 0;
        }
    }
    while (!que.empty()) {
        int now = que.front(); que.pop();
        for (int i = 0; i < 26; i++) {
            if (trie[now][i]) {
                fail[trie[now][i]] = trie[fail[now]][i];
                que.push(trie[now][i]);
            } else {
                trie[now][i] = trie[fail[now]][i];
            }
        }
    }
}

int query(char *s) {
    int now = 0, ans = 0;
    int len = strlen(s);
    for (int i = 0; i < len; i++) {
        int id = s[i] - 'a';
        now = trie[now][id];
        int temp = now;
        while (temp) {
            ans += flag[temp];
            flag[temp] = 0;
            temp = fail[temp];
        }
    }
    return ans;
}
char s[1000000+10];
int main() {
    int T;
    scanf("%d", &T);
    while (T--) {
        memset(trie, 0, sizeof trie);
        memset(fail, 0, sizeof fail);
        memset(flag, 0, sizeof flag);
        tol = 0;
        int n;
        scanf("%d", &n);
        for (int i = 0; i < n; i++) {
            scanf("%s", s);
            Insert(s);
        }
        getfail();
        scanf("%s", s);
        printf("%d\n", query(s));
    }
    return 0;
}