Rust入門中の2回目。ってか間が空くのが長いな!
食事する哲学者
完全な写経中だけど、ちゃんと理解して自力でRustのコードが書ける日は来るのだろうか?
しかも私の環境では全然並列実行出来ていない感があるのだけど、大丈夫なのかしらん?
use std::thread;
use std::time::Duration;
use std::sync::{Mutex, Arc};
struct Philosopher {
name: String,
left: usize,
right: usize,
}
impl Philosopher {
fn new(name: &str, left: usize, right: usize) -> Philosopher {
Philosopher {
name: name.to_string(),
left: left,
right: right,
}
}
fn eat(&self, table: &Table) {
let _left = table.forks[self.left].lock().unwrap();
thread::sleep(Duration::from_millis(150));
let _right = table.forks[self.right].lock().unwrap();
println!("{} is eating.", self.name);
thread::sleep(Duration::from_millis(1000));
println!("{} is done eating.", self.name);
}
}
struct Table {
forks: Vec<Mutex<()>>,
}
fn main () {
let table = Arc::new(Table { forks: vec![
Mutex::new(()),
Mutex::new(()),
Mutex::new(()),
Mutex::new(()),
Mutex::new(()),
]});
let philosophers = vec![
Philosopher::new("Judith Butler", 0, 1),
Philosopher::new("Gilles Deleuze", 1, 2),
Philosopher::new("Karl Marx", 2, 3),
Philosopher::new("Emma Goldman", 3, 4),
Philosopher::new("Michel Foucault", 0, 4),
];
let handles: Vec<_> = philosophers.into_iter().map(|p| {
let table = table.clone();
thread::spawn(move || {
p.eat(&table);
})
}).collect();
for h in handles {
h.join().unwrap();
}
}