#include <iostream>
#include <cstdio>
#include <map>

using namespace std;

int n,tip,numar,rest;
map <int, int> x;

int main()
{
    int i,z,j;
    FILE *f=fopen("hashuri.in","r");
    FILE *g=fopen("hashuri.out","w");
	fscanf(f,"%d ",&n);

	for(i=1;i<=n;i++)
	{
		fscanf(f,"%d%d",&tip,&numar);
		if(tip==1 && x.find(numar)==x.end())
            x[numar]=++j;
		else if(tip==2)
            x.erase(numar);
		else if(tip==3)
            fprintf(g,"%d\n",x.find(numar)!=x.end());
	}
    return 0;
}