#include <stdio.h>
#include <map>
using namespace std;
std::map<int,int> MyMap;

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

    for(; N; --N ){
            scanf("%d%d", &OPTION, &VALUE );
        if( OPTION == 1  ){  if( MyMap.find( VALUE ) == MyMap.end() )  MyMap[VALUE]=1; continue;    }
        if( OPTION == 2  ){  MyMap.erase(VALUE); continue; }
        if( OPTION == 3  )   printf("%d\n", (MyMap.find( VALUE ) != MyMap.end()) );
    }

    return 0;
}