[C++知识库]AC模板题p3808

#include <iostream>
#include <istream>
#include <sstream>
#include <vector>
#include <stack>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
#include <algorithm>
#include <numeric>
#include <chrono>
#include <ctime>
#include <cmath>
#include <cctype>
#include <string>
#include <cstdio>
#include <iomanip>


#include <thread>
#include <mutex>
#include <condition_variable>
#include <functional>
#include <iterator>
using namespace std;
const int maxn = 1e6 + 7;
int cnt = 0;
struct ACNode {
	int fail, num;
	int vis[26];//开始使用char 一直报错 干
}ac[maxn];

void Insert(string &input) {
	int cur = 0;
	for (int i = 0; i < input.size(); i++) {
		int index = input[i] - 'a';
		if (ac[cur].vis[index] == 0)ac[cur].vis[index] = ++cnt;
		cur = ac[cur].vis[index];
	}
	ac[cur].num++;
}

void GetFail() {
	int cur = 0;
	queue<int> q;
	for (int i = 0; i < 26; i++) {
		if (ac[cur].vis[i]) {
			int index = ac[cur].vis[i];
			ac[index].fail = 0;
			q.push(index);
		}
	}

	while (!q.empty()) {
		cur = q.front();
		q.pop();

		for (int i = 0; i < 26; i++) {
			if (ac[cur].vis[i]) {
				int son = ac[cur].vis[i];
				ac[son].fail = ac[ac[cur].fail].vis[i];
				q.push(son);
			}
			else {
				ac[cur].vis[i] = ac[ac[cur].fail].vis[i];
			}
		}
	}
}

int query(string &s)//AC自动机匹配
{
	int len = s.length();
	int cur = 0, ans = 0;
	for (int i = 0; i < len; ++i)
	{
		cur = ac[cur].vis[s[i] - 'a'];
		ans += ac[cur].num;
		ac[cur].num = 0;
	}
	return ans;
}

int main()
{
	int n;
	string s;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> s;
		Insert(s);
	}
	ac[0].fail = 0;
	GetFail();
	cin >> s;
	cout << query(s) << endl;
	return 0;
}