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

set<int> multime;
int n;
int tip, numar;

int main()
{
    freopen("hashuri.in", "r", stdin);
    freopen("hashuri.out", "w", stdout);
    scanf("%d", &n);
    set<int>::iterator it;
    for (int i = 0; i < n; i++)
    {
        scanf("%d", &tip);
        switch(tip)
        {
            case(1): scanf("%d", &numar); multime.insert(numar); break;
            case(2): scanf("%d", &numar); multime.erase(numar); break;
            case(3): scanf("%d", &numar); it = multime.find(numar); if (it == multime.end()) printf("%d\n", 0); else printf("%d\n", 1); break;
            default:break;
        }
    }
    return 0;
}