#include <bits/stdc++.h>

using namespace std;
ifstream a("hashuri.in");
ofstream b("hashuri.out");
unordered_set<int> s;
int n,t,x;
int main()
{
    a>>n;
    for( ; n; n--)
    {
        a>>t>>x;
        if(t==1)
            s.insert(x);
        else if(t==2)
            s.erase(x);
        else if(s.find(x)==s.end())
            b<<"0\n";
        else
            b<<"1\n";
    }
    return 0;
}