#include<bits/stdc++.h>
using namespace std;




set <int> v;
int ulti;
void adauga(int x){
    if(v.find(x)==v.end())
    v.insert(x);
}
void sterge(int x){
    if(v.find(x)==v.end())
    v.erase(x);
}
bool cauta(int x){
    if(v.find(x)!=v.end())
        return 1;
    else return 0;
}


int main() {

    int n;
    ifstream in("hashuri.in");
    ofstream out("hashuri.out");


    in>>n;
    for(int i=0;i<n;++i){
        int com,x;
        in>>com>>x;
        if(com==1) adauga(x);
        if(com==2) sterge(x);
        if(com==3) out<<cauta(x)<<"\n";
    }




    return 0;
}