#include <bits/stdc++.h>

using namespace std;
map <int,int> harta;
int q,tip,nr,k;
int main () {
	freopen("hashuri.in","r",stdin);
	freopen("hashuri.out","w",stdout);
	scanf("%d", &q);
	for(int i=1;i<=q;++i){
		scanf("%d%d", &tip, &nr);
		if(tip==1 && harta.find(nr)==harta.end())
			harta[nr]=++k;
		else if (tip==2)
			harta.erase(nr);
		else {
			if(harta.find(nr)!=harta.end())
				printf("1\n");
			else
				printf("0\n");
		}
	}
	return 0;
}