/*D
#include <cstdio>
#include <set>
#include <cstring>
#include <algorithm>
using namespace std;
const int N  = 1e6 + 10;
const int x = 123;
struct Str {
    char s[50];
};
Str str[N];
unsigned long long xp[50], H[50];
multiset<unsigned long long> ms;
void init() {
    xp[0] = 1;
    for(int i = 1; i < 50; ++i) xp[i] = xp[i - 1] * x;
}
int main() {
    //freopen("in.txt", "r", stdin);
    int n; scanf("%d", &n);
    ms.clear();
    init();
    for(int i = 0; i < n; ++i) {
        scanf("%s", str[i].s);
        int len = strlen(str[i].s);
        sort(str[i].s, str[i].s + len);
        H[len] = 0;
        for(int j = len - 1; j >= 0; --j) H[j] = H[j + 1] * x + str[i].s[j];
        unsigned long long h = H[0] - H[len] * xp[len];
        printf("%d\n", ms.count(h));
        ms.insert(h);
    }
    return 0;
}
*/

/*A
#include <cstdio>
#include <set>
#include <cstring>
#include <algorithm>
using namespace std;
const int N = 1e5 + 10;
char s[N];
int H[N];
int powm(int a, int b) {
    int ans = 1;
    while(b) {
        if(b & 1) ans = ans * a % 9973;
        a = a * a % 9973;
        b >>= 1;
    }
    return ans;
}
int main() {
   // freopen("in.txt", "r", stdin);
    int n;
    while(~scanf("%d", &n)) {
        scanf("%s", s + 1);
        int len = strlen(s + 1);
        H[0] = 1;
        for(int i = 1; i <= len; ++i) H[i] = (H[i - 1] * (s[i] - 28)) % 9973;
        H[0] = 0;
        while(n --) {
            int a, b;
            scanf("%d%d", &a, &b);
            if(a == 1) printf("%d\n", H[b]);
            else
            printf("%d\n", (H[b] * powm(H[a - 1], 9971)) % 9973);
        }
     }
     return 0;
}
*/



#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <vector>
#include <string>
#include <map>
using namespace std;
const int MAXS = 100005;
typedef struct node{
    char c;
    node* next[26];
    int num;
}*pnode;
pnode root;
char s[50];
void init(pnode &p)
{
    for(int i = 0; i < 26; ++i) p->next[i] = 0;
    p->num = 0;
}
void _insert(char *s)
{
    pnode p = root, t;
    int len = strlen(s);
    for(int i = 0; i < len; ++i)
    {
        if(p->next[s[i] - 97] == NULL) {
            t = new node;
            init(t);
            t->c = s[i];
            p->next[s[i] - 97] = t;
        }
        p = p->next[s[i] - 97];
        p->num++;
    }
}
int _search(char *s)
{
    pnode p = root;
    int len = strlen(s);
    for(int i = 0; i < len; ++i)
    {
        if(p->next[s[i] - 97] == NULL) return 0;
        p = p->next[s[i] - 97];
    }
    return p->num > 0;
}
void _delete(char *s) {
    pnode p = root;
    int len = strlen(s), cnt;
    for(int i = 0; i < len; ++i)
    {
        if(p->next[s[i] - 97] == NULL) return ;
        p = p->next[s[i] - 97];
    }
    cnt = p->num;
    for(int i = 0; i < 26; ++i) p->next[i] = NULL;
    p = root;
    for(int i = 0; i < len; ++i)
    {
        p = p->next[s[i] - 97];
        p->num -= cnt;
    }
}
int main()
{
  //  freopen("in.txt", "r", stdin);
    root = new node;
    init(root);
    int n; scanf("%d", &n);
    while(n --) {
        char op[10];
        scanf("%s%s", op, s);
        if(strcmp(op, "insert") == 0) _insert(s);
        else if(strcmp(op, "delete") == 0) _delete(s);
        else {
                if(_search(s)) puts("Yes");
                else puts("No");
        }
    }
    return 0;
}