#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;

struct Node
{
    struct Node *next[26];
    int num;
};
Node *head;

void Tree_Init()
{
    head = new Node;
    for (int i = 0; i < 26; ++i)
    {
        head->next[i] = NULL;
        head->num = 0;
    }
}

void Tree_Insert(char str[])
{
    Node *t, *s = head;
    int len = strlen(str);
    for (int i = 0; i < len; i++)
    {
        int id = str[i] - 'a';
        if (s->next[id] == NULL)
        {
            t = new Node;
            for (int j = 0; j < 26; j++)
                t->next[j] = NULL;
            t->num = 0;
            s->next[id] = t;
        }
        s = s->next[id];
        s->num++;
    }
}

int Tree_Find(char str[])
{
    Node *s = head;
    int cnt, len = strlen(str);
    for (int i = 0; i < len; ++i)
    {
        int id = str[i] - 'a';
        if (s->next[id] == NULL) return 0;
        else
        {
            s = s->next[id];
            cnt = s->num;
        }
    }
    return cnt;
}

void Tree_Del(char str[], int cnt)
{
    Node *s = head;
    int len = strlen(str);
    for (int i = 0; i < len; i++)
    {
        int id = str[i] - 'a';
        s = s->next[id];
        s->num -= cnt;
    }
    for(int i = 0; i < 26; i++)
        s->next[i] = NULL;
}

int main()
{
    //freopen("in.txt", "r", stdin);
    Tree_Init();
    int n;
    char op[10], str[50];
    scanf("%d", &n);
    for(int i = 1; i <= n; i++)
    {
        scanf("%s%s", op, str);
        if(op[0] == 'i') Tree_Insert(str);
        else if(op[0] == 'd')
        {
            int cnt = Tree_Find(str);
            if(cnt > 0) Tree_Del(str, cnt);
        }
        else
        {
            if(Tree_Find(str) > 0) puts("Yes");
            else puts("No");
        }
    }
    return 0;
}