#include <iostream>
#include <fstream>
#include <map>
using namespace std;
ifstream fin("hashuri.in");
ofstream fout("hashuri.out");
map<int,int> h;
int n,t,x,i;
int main()
{
    fin>>n;
    for(i=1;i<=n;i++)
    {
        fin>>t>>x;
        if(t==1) h.insert(make_pair(x,0));
        else if(t==2) h.erase(x);
        else if(h.find(x)==h.end()) fout<<"0\n";
        else fout<<"1\n";
    }
    return 0;
}