trie树

35 阅读1分钟
#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
#include<stdio.h>
using namespace std;
const int N = 100010;
int son[N][26], cnt[N], idx;
char str[N];
void insert(char str[])
{
	int p = 0;
	for (int i = 0; str[i]; i++)
	{
		int u = str[i] - 'a';
		if (!son[p][u])
		{
			son[p][u] = ++idx;
		}
		p = son[p][u];
	}
	cnt[p]++;
}
int query(char str[])
{
	int p = 0;
	for (int i = 0; str[i]; i++)
	{
		int u = str[i] - 'a';
		if (!son[p][u])
		{
			return 0;
		}
		p = son[p][u];
	}
	return cnt[p];
}
int main()
{
	int n;
	scanf("%d", &n);
	while (n--)
	{
		char op[2];
		scanf("%s%s", op, str);
		if (op[0] == 'i')insert(str);//输入i表示插入操作,其他表示查找
		else printf("%d\n", query(str));
	}
	return 0;
}