#include <bits/stdc++.h>

using namespace std;

ifstream fin("a.in");
ofstream fout("a.out");

/**int fastexpo(int a, int n)
{
    int p = 1;
    while(n)
    {
        if(n % 2 == 1) p = 1LL * p * a % mod;
        a = 1LL * a * a % mod;
        n /= 2;
    }
    return p;
}*/

int n;
set <int> s;

int main()
{
    int op, x;
    fin >> n;
    while(n--)
    {
        fin >> op >> x;
        if(op == 1) s.insert(x);
        else if(op == 2) s.erase(x);
        else
        {
            if(s.find(x) != s.end())
                fout << "1\n";
            else
                fout << "0\n";
        }
    }
    return 0;
}