use std::thread::spawn;

use crossbeam_channel::{bounded, Receiver};

type S0 = Receiver<Receiver<Receiver<Receiver<()>>>>;
type S1 = Receiver<Receiver<Receiver<()>>>;
type S2 = Receiver<Receiver<()>>;
type S3 = Receiver<()>;
type S4 = ();

fn main() {
    let main = spawn(move || {
        let (sender_s_0, receiver_s_0) = bounded::<S0>(1);
        let (sender_s_1, receiver_s_1) = bounded::<S1>(1);
        let (sender_s_2, receiver_s_2) = bounded::<S2>(1);
        let (sender_s_3, receiver_s_3) = bounded::<S3>(1);
        let (sender_s_4, receiver_s_4) = bounded::<S4>(1);

        sender_s_0.send(receiver_s_1).unwrap();
        let receiver_s_1_bis = receiver_s_0.recv().unwrap();

        sender_s_1.send(receiver_s_2).unwrap();
        let receiver_s_2_bis = receiver_s_1_bis.recv().unwrap();

        sender_s_2.send(receiver_s_3).unwrap();
        let receiver_s_3_bis = receiver_s_2_bis.recv().unwrap();

        sender_s_3.send(receiver_s_4).unwrap();
        let receiver_s_4_bis = receiver_s_3_bis.recv().unwrap();

        sender_s_4.send(()).unwrap();
        receiver_s_4_bis.recv().unwrap();
    });

    main.join().unwrap();
}