#include <bits/stdc++.h>
using namespace std;
int n,cnt,type,aux;
map <int, int> Hash;
int main() {
    ifstream cin("hashuri.in");
    ofstream cout("hashuri.out");
    cin>>n;
    for (int i= 1;i<=n;++i) {
        cin>>type>>aux;
        switch (type){
           case 1 : Hash[aux] = ++cnt; break;
           case 2 : Hash.erase(aux); break;
           case 3 : cout<<(Hash[aux]>0)<<"\n"; break;
           default : break;
       }
    }
    return 0;
}