#include<cstdio>
#include<map>

using namespace std;

int n, ct;

map <int,int> h;

int main()
{
	freopen("hashuri.in","r",stdin);
	freopen("hashuri.out","w",stdout);
	
	int tip, val;
	
	scanf("%d",&n);
	
	while(n--)
	{
		scanf("%d%d",&tip,&val);
		
		if(tip==1 && h.find(val)==h.end())
			h[val]=ct++;
		else if(tip==2)
			h.erase(val);
		else if(tip==3)
			printf("%d\n",h.find(val)!=h.end());
	}
	
	return 0;
}