use std::mem::{size_of, MaybeUninit};

const B: usize = 6;
pub const CAPACITY: usize = 2 * B - 1;

#[repr(C)]
struct LeafNodeA<K, V> {
    parent: *const (),
    parent_idx: MaybeUninit<u16>,
    len: u16,
    keys: [MaybeUninit<K>; CAPACITY],
    vals: [MaybeUninit<V>; CAPACITY],
}

#[repr(C)]
struct LeafNodeB<K, V> {
    parent: *const (),
    parent_idx: MaybeUninit<u16>,
    len: u16,
    shared_root: bool,
    keys: [MaybeUninit<K>; CAPACITY],
    vals: [MaybeUninit<V>; CAPACITY],
}

macro_rules! compare_sizes {
    ($k:ty, $v:ty) => {
        println!("LeafNode<{}, {}>", stringify!($k), stringify!($v));
        println!("   current: {:?}", size_of::<LeafNodeA<$k, $v>>());
        println!(" with flag: {:?}", size_of::<LeafNodeB<$k, $v>>());
    }
}

fn main() {
    compare_sizes!(u16, u16);
}