#include <iostream>
#include <fstream>
#include <map>
#include <cstdio>
using namespace std;

FILE *fin, *fout;



int main() {
    int n, x, op;
    map<int, int> m;
    fin = fopen("hashuri.in", "r");
    fout = fopen("hashuri.out", "w");
    fscanf(fin, "%d", &n);
    for(int i=0; i<n; ++i)
    {
        fscanf(fin, "%d%d", &op, &x);
        if (op == 1)
        {
            if(m.find(x)==m.end())
                m[x] = 1;

        }

        else if (op == 2)
        {
                m.erase(x);
        }
        else
        {
            if( m.find(x)!=m.end())
                fprintf(fout, "1\n");
            else
                fprintf(fout, "0\n");
        }


    }


    return 0;
}