#include <iostream>
#include <stdio.h>
#include <cstdlib>

struct Link {
    Link(int value) {
        this->value = value;
        this->next = NULL;
    }
    int value;
    Link* next;
};

Link* hashTable[10000];

int getHashTableIndex(int key) { return abs(key) % 9721; }

bool existCmd(int key) {
    int index = getHashTableIndex(key);

    if (!hashTable[index]) {
        return false;
    }
    else {
        Link *curLink = hashTable[index];
        while (true) {
            if (curLink->value == key) return true;

            if (!curLink->next) return false;
            else curLink = curLink->next;
        }
    }
}

void insertCmd(int key) {
    if (existCmd(key)) return;

    int index = getHashTableIndex(key);

    if (!hashTable[index]) {
        hashTable[index] = new Link(key);
    }
    else {
        Link* curLink = hashTable[index];
        while (curLink->next) curLink = curLink->next;
        curLink->next = new Link(key);
    }
}


void deleteCmd(int key) {
    if (existCmd(key)) {
        int index = getHashTableIndex(key);

        Link *curLink = hashTable[index];
        if (curLink->value == key) {
            hashTable[index] = curLink->next;
            delete curLink;
            return;
        }

        while (true) {
            Link* nextLink = curLink->next;
            if (nextLink->value == key) {
                curLink->next = nextLink->next;
                delete nextLink;
                nextLink = NULL;
                return;
            }
            curLink = nextLink;
        }
    }
}



int main() {
    std::ios_base::sync_with_stdio(0);

    freopen("/Users/Alex/ClionProjects/cpp_binary/input.txt", "r", stdin);
    freopen("/Users/Alex/ClionProjects/cpp_binary/output.txt", "w", stdout);

    //freopen("set.in", "r", stdin);
    //freopen("set.out", "w", stdout);

    int x;
    std::string cmd;
    while (std::cin >> cmd) {
        std::cin >> x;
        switch (cmd[0]) {
            case 'i':
                insertCmd(x);
                break;
            case 'd':
                deleteCmd(x);
                break;
            case 'e':
                if (existCmd(x)) std::cout << "true\n";
                else std::cout << "fasle\n";
                break;
        }
    }

    return 0;
}