#include <cstdio>
#include <unordered_set>
using namespace std;

int n;
unordered_set <int> uset;
int main(){
	freopen("hashuri.in","r",stdin);
	freopen("hashuri.out","w",stdout);
	scanf("%d",&n);
	int x,y;
	while(n--){
		scanf("%d%d",&x,&y);
		switch(x){
			case 1: uset.insert(y); break;
			case 2: uset.erase(y); break;
			case 3: if(uset.find(y) != uset.end()) printf("1\n"); else printf("0\n"); break;
		}
	}
	return 0;
}