#include<cstdio>
#include<set>
using namespace std;
set<int> v;
set<int>::iterator it;
int main ()
{freopen ("hashuri.in","r",stdin);
freopen ("hashuri.out","w",stdout);
int n,i,x,y;
scanf("%d",&n);
for(i=1;i<=n;i++)
    {scanf("%d%d",&x,&y);
    if(x==1)
        v.insert(y);
    else
        if(x==2)
            {it=v.find(y);
            if(it!=v.end())
                v.erase(y);
            }
        else
            {it=v.find(y);
            if(it!=v.end())
                printf("1\n");
            else
                printf("0\n");
            }
    }
return 0;
}