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#include <iostream>
#include <vector>
using namespace std;
const int ALPHABET_SIZE = 26;
struct node {
    node *children_of_this_node[ALPHABET_SIZE];
    bool end_of_word;

node() {
        end_of_word = false;
        for(int i = 0; i < ALPHABET_SIZE; i++) {
            children_of_this_node[i] = NULL;
        }
    }
};
void insert_word(node * trie, string s) {
    node * tmp = trie;
    
    for(int i = 0; i < (int) s.size(); i++) {
        int current_char = (s[i] - 'a');
        if(tmp -> children_of_this_node[current_char] == NULL) {
            tmp -> children_of_this_node[current_char] = new node();
        }
        tmp = tmp -> children_of_this_node[current_char];
    }
    tmp -> end_of_word = true;
}
bool search_word(node * trie, string s) {
    node * tmp = trie;
    
    for(int i = 0; i < (int) s.size(); i++) {
        int current_char = (s[i] - 'a');
        if(tmp -> children_of_this_node[current_char] == NULL) {
            return false;
        }
        tmp = tmp -> children_of_this_node[current_char];
    }
    return tmp -> end_of_word;
}
void delete_word(node * trie, string s) {
    node * tmp = trie;
    
    for(int i = 0; i < (int) s.size(); i++) {
        int current_char = (s[i] - 'a');
        if(tmp -> children_of_this_node[current_char] == NULL) {
            return;
        }
        tmp = tmp -> children_of_this_node[current_char];
    }
    tmp -> end_of_word = false;
}
int main() {
    int n;
    cin >> n;
    
    node * trie = new node();
    vector<string> dictionary(n);
    for(int i = 0; i < n; i++) {
        cin >> dictionary[i];
        insert_word(trie, dictionary[i]);
    }
    
    int q;
    cin >> q;
    for(int i = 0; i < q; i++) {
        char c;
        cin >> c;
        if(c == 'D') {
            string s;
            cin >> s;
            delete_word(trie, s);
        }
        else {
            string s;
            cin >> s;
            if(search_word(trie, s)) {
                cout << "YES" << endl;
            }
            else {
                cout << "NO" << endl;
            }
        }
    }

return 0;
}