#include <bits/stdc++.h>///set
using namespace std;
ifstream fin ("hashuri.in");
ofstream fout("hashuri.out");
set<int> v;
int main()
{
    int n;
    fin>>n;
    for(int i=1;i<=n;i++)
    {
        int op,x;
        fin>>op>>x;
        if(op==1)
            v.insert(x);
        else
            if(op==2)
                v.erase(x);
            else
                if(v.find(x)==v.end())
                    fout<<0<<'\n';
                else
                    fout<<1<<'\n';
   }
}