use std::rc::Rc;

struct A;

fn p<X>(x: X) {
    match std::mem::size_of::<X>() {
        0 => print!("0"),
        _ => print!("1"),
    }
}

fn main() {
    let a = &A;
    p(a);
    p(a.clone());
    
    let b = &();
    p(b);
    p(b.clone());
    
    let c = Rc::new(());
    p(Rc::clone(&c));
    p(c.clone());
}