#include <stdio.h>
#include <set>
using namespace std;
set <int> myset;
FILE *fin = fopen("hashuri.in", "r");
FILE *fout = fopen("hashuri.out", "w");
int main()
{
    int n,tip;
    fscanf(fin, "%d", &n);
    for(int i=1;i<=n;i++)
    {
        fscanf(fin, "%d", &tip);
        int x;
        if(tip == 1)
        {
            fscanf(fin, "%d", &x);
            myset.insert(x);
        }
        if(tip == 2)
        {
            fscanf(fin, "%d", &x);
            myset.erase(x);
        }
        if(tip == 3)
        {
            fscanf(fin, "%d", &x);
            if(myset.count(x)!=0) fprintf(fout, "1\n");
            else fprintf(fout, "0\n");
        }
    }
    return 0;
}