#include <stdio.h>
#include <iostream>
#include <string>
#include <string.h>
#include <algorithm>
#include <map>
#include <vector>
#include <set>
#include <queue>
using namespace std;

int n;
char op[10], str[40];

struct Node {
    int cnt;
    map<char,Node*> next;
    Node() { cnt = 0; }
} *root = new Node();

void insert() {
    int i, size = strlen(str);
    Node* cur = root;
    for (i = 0; i < size; ++i) {
        if (cur->next.count(str[i]) == 0) {
            Node* child = new Node();
            cur->next[str[i]] = child;
        }
        cur = cur->next[str[i]];
        cur->cnt++;
    }
}

int search() {
    int i, size = strlen(str);
    Node* cur = root;
    for (i = 0; i < size; ++i) {
        if (cur->next.count(str[i]) == 0)
            return 0;
        cur = cur->next[str[i]];
        if (cur->cnt == 0) return 0;
    }
    return cur->cnt;
}

void mremove(Node* p) {
    for (map<char,Node*>::iterator it = p->next.begin(), ie = p->next.end(); it != ie; ++it) {
        mremove(it->second);
        delete it->second;
    }
    p->next.clear();
}

void mdelete() {
    int i, size = strlen(str), c = search();
    if (c == 0) return;
    Node* cur = root;
    for (i = 0; i < size; ++i) {
        cur = cur->next[str[i]];
        cur->cnt -= c;
    }
    mremove(cur);
}

int main() {
    scanf("%d", &n); while (n--) {
        scanf("%s %s", op, str);
        switch(op[0]) {
            case 'i': insert(); break;
            case 's': printf((search() > 0?"Yes\n": "No\n")); break;
            case 'd': mdelete();
        }
    }
}