#include <iostream>
#include <hash_map>
#include <fstream>
using namespace std;
using namespace __gnu_cxx;

ifstream fin("hashuri.in");
ofstream fout("hashuri.out");

int n, op, x;

int main()
{
    hash_map<int, bool> hashTable;
    fin>>n;
    while (n) {
        fin>>op>>x;
        switch (op) {
            case 1:
                hashTable.insert({x, 1});
                break;
            case 2:
             //   if (hashTable.count(x))
                hashTable.erase(x);
                break;
            case 3:
                if (hashTable.count(x))
                    fout<<hashTable[x]<<"\n";
                else
                    fout<<0<<"\n";
                break;
        }
        n--;
    }
    return 0;
}