#include <stdio.h>
#include <stdlib.h>
#include <unordered_set>

int main()
{
	FILE *f = fopen("hashuri.in", "r"), *g = fopen("hashuri.out", "w");
	int n,x,i,op;
	fscanf(f, "%d", &n);
	std::unordered_set<int> hash;
	for (i = 0; i < n; i++)
	{
		fscanf(f, "%d", &op);
		fscanf(f, "%d", &x);
		if (op==1)
		   hash.insert(x);
		if (op == 2)
			hash.erase(x);
		if (op == 3)
		{
			if (hash.find(x) != hash.end())
				fprintf(g, "1\n");
			else fprintf(g, "0\n");
		}
	}
	fclose(f);
	fclose(g);
	return 0;
}