#include <iostream>
#include <fstream>
#include <vector>
#include <unordered_map>
using namespace std;
ifstream in("hashuri.in");
ofstream out("hashuri.out");
unordered_map<int,bool> u;
int main(){
    int n, x, y;
    in>>n;
    for(int i=1; i<=n; i++){
        in>>x>>y;
        if(x==1)u[y]=true;
        else if(x==2)u.erase(y);
        else out<<u[y]<<"\n";
    }
    return 0;
}