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#include <iostream>
#include <queue>
#include <vector>
#include <map>
using namespace std;
const int alphabet_size = 26;
struct node {
    bool is_end_of_word;
    node * children_of_node[alphabet_size];
    node() {
        is_end_of_word = false;
        for(int i = 0; i < alphabet_size; i++) {
            children_of_node[i] = NULL;
        }
    }
};
void insert_word(node * trie, string word) {
    node * tmp = trie;
    for(int i = 0; i < (int) word.size(); i++) {
        int c = word[i] - 'a';
        if(tmp -> children_of_node[i] == NULL) {
            tmp -> children_of_node[i] = new node();
        }
        tmp = tmp -> children_of_node[i];
    }
    tmp -> is_end_of_word = true;
}
bool search_word(node * trie, string word) {
    node * tmp = trie;
    for(int i = 0; i < (int) word.size(); i++) {
        int c = word[i] - 'a';
        if(tmp -> children_of_node[i] == NULL) {
            return false;
        }
        tmp = tmp -> children_of_node[i];
    }
    return tmp -> is_end_of_word;
}
void delete_word(node * trie, string word) {
    node * tmp = trie;
    for(int i = 0; i < (int) word.size(); i++) {
        int c = word[i] - 'a';
        if(tmp -> children_of_node[i] == NULL) {
            return;
        }
        tmp = tmp -> children_of_node[i];
    }
    tmp -> is_end_of_word = false;
}
int main() {
    ios_base::sync_with_stdio(false);
    node * trie = new node();
    
    while(true) {
        string a, b;
        cin >> a >> b;
        if(a == "insert") {
            insert_word(trie, b);
        }
        else if(a == "delete") {
            delete_word(trie, b);
        }
        else {
            cout << search_word(trie, b) << endl;
        }
    }
    return 0;
}