#include <bits/stdc++.h>
#include <unordered_set>
using namespace std;
ifstream fin("hashuri.in");
ofstream fout("hashuri.out");
unordered_set <int> s;
int n,task,x;

int main() {
    fin>>n;
    while(n--){
        fin>>task>>x;
        if(task==1){
            s.insert(x);
        }
        else if(task==2){
            s.erase(x);
        }
        else if(task==3){
            if(s.find(x)==s.end())
                fout<<0<<'\n';
            else
                fout<<1<<'\n';
        }
    }
    return 0;
}