#include <fstream>
#include <iomanip>
#include <cmath>
#include <algorithm>
#include <string>
#include <vector>
#include <cstring>
#include <bitset>
#include <unordered_set>
using namespace std;

ifstream cin("hashuri.in");
ofstream cout("hashuri.out");

unordered_set <int> f;

int main(){
    int n;
    cin >> n;
    while(n--){
        int x, y;
        cin >> x >> y;
        if(x == 1){
            f.insert(y);
        }
        else if(x == 2){
            f.erase(y);
        }
        else{
            if(f.find(y) != f.end()){
                cout << "1\n";
            }
            else{
                cout << "0\n";
            }
        }
    }
    return 0;
}