#include <bits/stdc++.h> //Andrei Alexandru a.k.a Sho10
#define ll long long int
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#define all(a) (a).begin(), (a).end()
#define sz size
#define f first
#define s second
#define pb push_back
#define er erase
#define in insert
#define mp make_pair
#define pi pair
#define rc(s) return cout<<s,0
#define endl '\n'
#define mod 1000000007
#define PI 3.14159265359
#define CODE_START  ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
using namespace std;
ll q;
set<ll>s;
int32_t main(){
CODE_START;
ifstream cin("hashuri.in");
ofstream cout("hashuri.out");
cin>>q;
while(q--){
    ll t,x;
    cin>>t>>x;
    if(t==1){
        s.insert(x);
    }else if(t==2){
    s.erase(x);
    }else {
    if(s.find(x)!=s.end()){
        cout<<1<<'\n';
    }else cout<<0<<'\n';
}
}
}