#include <stdio.h>
#include <set>
using namespace std;

int N;
set<int> A;

int main()
{
    int tip, x;
    freopen("hashuri.in","r",stdin);
    freopen("hashuri.out","w",stdout);
    scanf("%d", &N);
    for ( ; N; --N)
    {
        scanf("%d %d", &tip, &x);
        if (tip == 1)
        {
            A.insert(x);
            continue;
        }
        if (tip == 2)
        {
            A.erase(x);
            continue;
        }
        if (A.find(x) != A.end()) printf("\n1");
            else printf("\n0");
    }

    return 0;
}