#include <map>
#include <cstdio>

using namespace std;

map<int, int> elements;
int z;

int main()
{
	freopen("hashuri.in", "r", stdin);
	freopen("hashuri.out", "w", stdout);

    int n, task, x;
    scanf("%d", &n);

    while (n--) {
    	scanf("%d%d", &task, &x);

    	if (task == 1) 
    		if (elements.find(x) == elements.end()) elements[x] = ++z;
    	if (task == 2) elements.erase(x);
    	if (task == 3) printf("%d\n", elements.find(x) != elements.end());
   	}

    return 0;
}