#include<stdio.h>
#include<map>
using namespace std;
int n,c;
map<int,int>m;
int main()
{
	freopen("hashuri.in","r",stdin);
	freopen("hashuri.out","w",stdout);
	int k,x;
	scanf("%d",&n);
	for(int i=1;i<=n;i++)
	{
		scanf("%d %d",&k,&x);
		if(k==1&&m.find(x)==m.end())m[x]=c++;
		if(k==2)m.erase(x);
		if(k==3)printf("%d\n",m.find(x)!=m.end());
	}
	return 0;
}