#include <bits/stdc++.h>
using namespace std;
ifstream f ( "hashuri.in" ); ofstream g ( "hashuri.out" );
map< int , int > H;
int main()
{   int n,tip,x,nr=0;
    f>>n;
    while(n--)
    {   f>>tip>>x;
        if(tip==1 and H.find(x)==H.end()) H[x]=++nr;
        if(tip==2) H.erase(x);
        if(tip==3) g<<H.find(x)!=H.end()<<'\n';
    }
    return 0;
}