#include <iostream>
#include <fstream>
#include <unordered_map>
using namespace std;
ifstream f("hashuri.in");
ofstream g("hashuri.out");
int n, x, t;
unordered_map<int, int> m;
int main()
{
    f>>n;
    while(n--){
        f>>t>>x;
        if(t==1) m[x]=1;
        if(t==2) m.erase(x);
        if(t==3) g<<(m.find(x)!=m.end())<<'\n';
    }
    return 0;
}