#include <map>
#include <stdio.h>

using namespace std;

int N,op,x;
map <int,int> M;

int main()
{
    freopen("hashuri.in", "r",stdin);
    freopen("hashuri.out", "w" , stdout);
    scanf("%d ",&N);

     for (int i=1; i<=N ; i++)
     {
         scanf("%d %d",&op,&x);
         if (op == 1 && M.find(x) == M.end()) M[x] = x;
         if (op == 2 ) M.erase(x);
         if (op == 3 ) printf("%d\n",M.find(x) != M.end());
     }
    return 0;
}