#include <bits/stdc++.h>
#include <iostream>
using namespace std;

int main()
{
    int n, op, x, nr = 0;
    unordered_map<int, int> hashMap;

    ifstream f("hashuri.in");
    ofstream o("hashuri.out");

    f >> n;
    for(int i = 0; i < n; i++){
        f >> op >> x;

        // verific operatiile si ma uit ce trebuie sa fac pt fiecare
        switch(op){
        case 1:
            // adaug elementul x la multime
            if(hashMap.find(x) == hashMap.end()){
                // daca nu il gasesc il adaug
                hashMap[x] = 1;
            }
            break;
        case 2:
            // sterg elementul x daca este in multime, altfel multimea ramane neschimbata
            hashMap.erase(x);
            break;
        case 3:
            o << (hashMap.find(x) != hashMap.end()) << endl;
            break;
        }
    }
    return 0;
}