use rand::{thread_rng, Rng};
use std::sync::mpsc;

fn main() {
    let (tx, rx) = mpsc::channel();

    for (work_id, tx) in std::iter::repeat(tx).take(25).enumerate() {
        std::thread::spawn(move || {
            let work_time_ms = thread_rng().gen_range(0, 500);
            std::thread::sleep(std::time::Duration::from_millis(work_time_ms));
            tx.send(work_id)
        });
    }

    while let Ok(work_id) = rx.recv() {
        println!("Work {} done", work_id)
    }
}