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

///数据结构
#define MAX 26
typedef struct Trie
{
    Trie *next[MAX];
    int v;   //根据需要变化
};

Trie root;

void createTrie(char *str)
{
    int len = strlen(str);
    Trie *p = &root, *q;
    for(int i=0; i<len; ++i)
    {
        int id = str[i]-'a';
        if(p->next[id] == NULL)
        {
            q = (Trie *)malloc(sizeof(Trie));
            q->v = 1;    //初始v==1
            for(int j=0; j<MAX; ++j)
                q->next[j] = NULL;
            p->next[id] = q;
            p = p->next[id];
        }
        else
        {
            p->next[id]->v++;
            p = p->next[id];
        }
    }
//    p->v++;
    //p->v = -1;   //若为结尾，则将v改成-1表示
}

int findTrie(char *str)
{
    int len = strlen(str);
    Trie *p = &root;
    for(int i=0; i<len; ++i)
    {
        int id = str[i]-'a';
        p = p->next[id];
        if(p == NULL)   //若为空集，表示不存以此为前缀的串
            return 0;
//        if(p->v == -1)   //字符集中已有串是此串的前缀
//            return -1;
    }
    return p->v;
}

int dealTrie(Trie* T)
{
    int i;
    if(T==NULL)
        return 0;
    for(i=0;i<MAX;i++)
    {
        if(T->next[i]!=NULL)
        {
            dealTrie(T->next[i]);
            T->next[i] = NULL;
        }
    }
    free(T);
    return 0;
}

int del(char *str, int val)
{
    int len = strlen(str);
    Trie *p = &root;
    int id;
    for(int i =0 ; i < len; i++)
    {
        id = str[i] - 'a';
        p->next[id]->v -= val;
        if(i != len-1) p = p->next[id];
    }
    dealTrie(p->next[id]);
    p->next[id] = 0;
}

char in[100], str[100];

int main(void)
{
    int n;
    scanf("%d", &n);
    for(int i = 0; i < 26; i++)
        root.next[i] = 0;
    while(n--)
    {

        scanf("%s%s", in, str);
        int len = strlen(str);
        if(in[0] == 'i')
        {
            createTrie(str);
        }
        else if(in[0] == 'd')
        {
            int val = findTrie(str);
            if(val)
            {
                del(str, val);
            }
        }
        else
        {
            int val = findTrie(str);
            if(val) printf("Yes\n");
            else printf("No\n");
        }
//        cout << ans << endl;
    }
    return 0;
}