#include <cstdio>
#include <cstring>
#include <string.h>
#include <iostream>
#include <algorithm>
#include <vector>
#include <stack>
#include <cmath>
#include <queue>
#include <set>
#include <map>
using namespace std;
#define ll long long
#define FOR(i,j,k) for(int i =j; i<=k ;i++)
#define ll long long
#define pii pair<int,int>
const int maxn = 1000010;
const ll mod = 1e9+7;
struct Trie{
    int ch[100005*10][30];
    int num[100005*10];
    int sz;
    Trie(){sz = 1; memset(ch[0], 0, sizeof(ch[0]));memset(num, 0, sizeof(num));}
    void insert(char *s)
    {
        int u= 0 ,n = strlen(s);
        FOR(i, 0, n-1)
        {
            int c= s[i] - 'a';
            if(!ch[u][c]){
                memset(ch[sz], 0 ,sizeof(ch[sz]));
                ch[u][c] = sz++;
            }
            u = ch[u][c];
            num[u] ++;
        }
    }
    void delet(char *s)
    {
        int u= 0 ,u2= 0,n = strlen(s);
        int c;
        int seq =0;
        FOR(i, 0, n-1)
        {
           // cout<<s[i]<<endl;
            c= s[i] - 'a';
            if(!ch[u][c]){
                return;
            }
            u2= u;
            u = ch[u][c];
            seq = num[u];
        }
        u = 0,u2 = 0;
        FOR(i, 0, n-1)
        {
            c= s[i] - 'a';
            u2= u;
            u = ch[u][c];
            num[u] -= seq;
        }
        //cout<<ch[u2][c]<<endl;
        ch[u2][c] = 0;
    }
    bool search(char *s)
    {
        int u= 0 ,n = strlen(s);
        FOR(i, 0, n-1)
        {
            //cout<<s[i]<<endl;
            int c= s[i] - 'a';
            if(!ch[u][c]){
                return 0;
            }
            u = ch[u][c];
            if(num[u] == 0) return 0;
        }
        return 1;
    }
}trie;
int main()
{
    int n;
    char op[30],s[40];
    scanf("%d",&n);
    while(n--)
    {
        scanf("%s%s",op,s);
        if(op[0] == 'i') trie.insert(s);
        if(op[0] == 's') {
           int x= trie.search(s);
            if(x == 1) cout<<"Yes"<<endl;
            else cout<<"No"<<endl;
        }
        if(op[0] == 'd'){
           // cout<<s<<endl;
            trie.delet(s);
        }
    }
    return 0;
}