#include <bits/stdc++.h>

using namespace std;

unordered_set<int> M;
ifstream fin("hashuri.in");
ofstream fout("hashuri.out");
int n,x,y;

int main()
{
    fin>>n;
    for(int i=1;i<=n;i+=1)
    {
        fin>>x>>y;
        if(x==1) M.insert(y);
        else if(x==2) M.erase(y);
        else
        {
            if(M.find(y)!=M.end()) fout<<1<<'\n';
            else fout<<0<<'\n';
        }
    }
    return 0;
}