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