#include <iostream>
#include <map>
#include <fstream>
using namespace std;
ifstream in("hashuri.in");
ofstream out("hashuri.out");
map<int,bool> v;
int main()
{
    int n,i,op,x;
    in>>n;
    for(i=0;i<n;i++)
    {
        in>>op>>x;
        switch(op)
        {
            case 1:v[x] = 1; break;
            case 2:v.erase(x); break;
            case 3:out<<(int)v[x]<<"\n"; break;
        }
    }
    return 0;
}