#include <bits/stdc++.h>


using namespace std;

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

int main()
{
    unordered_set < int > us;
    int n,index,value;
    fin>>n;
    for(int i=1;i<=n;i++)
    {
        fin>>index>>value;
        if(index == 1)
        {
            if(us.count(value)==0)
            {
                us.insert(value);
            }
        }
        else if(index == 2)
        {
            if(us.count(value)==1)
            {
                us.erase(value);
            }
        }
        else
        {
            if(us.count(value)==1)
                fout<<1<<endl;
            else
                fout<<0<<endl;
        }
    }
}