#include <stdio.h>   
#include <map>   
  
using namespace std;   
  
int N, NR;   
map <int, int> M;   
  
int main()   
{   
    freopen("hashuri.in", "r", stdin);   
    freopen("hashuri.out", "w", stdout);   
  
    int i, tip, x;   
  
    scanf("%d ", &N);   
  
    for (i = 1; i <= N; i++)    
    {   
        scanf("%d %d ", &tip, &x);   
  
        if (tip == 1 && M.find(x)==M.end()) M[x] = ++NR;   
        if (tip == 2) M.erase(x);   
        if (tip == 3) printf("%d\n", M.find(x) != M.end());   
    }   
  
    return 0;