1 #include <iostream>
2 #include <algorithm>
3 #include <cstring>
4 #include <string>
5 #include <vector>
6
7 using namespace std;
8 typedef long long ll;
9
10 const int maxn = 1300005;
11 int pos = 1;
12
13 int trie[maxn][26];
14 int num[maxn];
15
16 void insert(string str)
17 {
18 int p = 0;
19 for (int i = 0; str[i]; i++)
20 {
21 int n = str[i] - 'a';
22 if (!trie[p][n])
23 {
24 trie[p][n] = pos++;
25 }
26 p = trie[p][n];
27 num[p]++;
28 }
29 }
30
31 int Find(string str)
32 {
33 int p = 0;
34 for (int i = 0; str[i]; i++)
35 {
36 int n = str[i] - 'a';
37 if (!trie[p][n])
38 return 0;
39 p = trie[p][n];
40 }
41 return num[p];
42 }
43
44 void Delete(string str)
45 {
46 int p = 0;
47 for (int i = 0; str[i]; i++)
48 {
49 int n = str[i] - 'a';
50 if (!trie[p][n]) return;
51 p = trie[p][n];
52 }
53 int cnt = num[p];
54 // 先跑一遍，看有没有这个string。
55 p = 0;
56 for (int i = 0; str[i]; i++)
57 {
58 int n = str[i] - 'a';
59 p = trie[p][n];
60 num[p] -= cnt;
61 }
62 for (int i = 0; i < 26; i++)
63 {
64 trie[p][i] = 0;
65 }
66 }
67
68 int main()
69 {
70 int t;
71 cin >> t;
72 string c, s;
73 while (t--)
74 {
75 cin >> c >> s;
76 if (c == "insert") insert(s);
77 else if (c == "search")
78 {
79 if (Find(s)) cout << "Yes" << endl;
80 else cout << "No" << endl;
81 }
82 else Delete(s);
83 }
84 return 0;
85 }
