#include <iostream>
#include <cstdio>
#include <map>
using namespace std;


int main(void)
{
	FILE *f = fopen("hashuri.in", "r");
	FILE *g = fopen("hashuri.out", "w");
	map<int, int> m;
	int N, poz = 0, op, x;
	fscanf(f, "%d", &N);
	for(int i = 1; i <= N; ++i)
	{
		fscanf(f, "%d%d", &op, &x);
		if(op == 1 && m.find(x) == m.end())
			m[x] = 1;
		if(op == 2)
			m.erase(x);
		if(op == 3)
			fprintf(g, "%d\n", m.find(x) != m.end());
	}
	
	fclose(f);
	fclose(g);
	return 0;
}