#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>

typedef long long ll;

const ll mod=1e9+7;

const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};

#define all(x) x.begin(),x.end()
#define allr(x) x.rbegin(),x.rend()
#define rc(x)  return cout<<x<<"\n",0
#define sz(s)  (int) s.size()
#define pb push_back
#define mp make_pair
#define fr first
#define sc second
#define PI 3.14159265358979

using namespace std;

ll t;
unordered_set<int>s;
int main() {
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	ifstream cin("hashuri.in");
	ofstream cout("hashuri.out");
	ll n;
	cin >> n;
	while (n--) {
		ll x,v;
		cin >> x >> v;
		if (x==1) {
			s.insert(v);
		}
		if (x==2 && s.count(v)) {
			s.erase(v);
		}
		if (x==3) {
			cout << (s.count(v)) << '\n';
		}
	}


}