#include <iostream>
#include <fstream>
#include <unordered_set>

using namespace std;

int main(){
    ifstream f("hashuri.in");
    ofstream g("hashuri.out");

    int n;
    unordered_set<int> H;

    f >> n;
    for (int i = 0; i < n; ++i){
        int x, y;
        f >> x >> y;
        if (x == 1)
            H.insert(y);
        if (x == 2)
            H.erase(y);
        if (x == 3)
            if (H.find(y) != H.end())
                g << 1 << "\n";
            else
                g << 0 << "\n";
    }

    f.close();
    g.close();

    return 0;
}