diff options
| -rw-r--r-- | exercises/threads/threads1.rs | 25 | ||||
| -rw-r--r-- | info.toml | 2 |
2 files changed, 17 insertions, 10 deletions
diff --git a/exercises/threads/threads1.rs b/exercises/threads/threads1.rs index e59f4ce..d6376db 100644 --- a/exercises/threads/threads1.rs +++ b/exercises/threads/threads1.rs @@ -1,31 +1,38 @@ // threads1.rs // Execute `rustlings hint threads1` or use the `hint` watch subcommand for a hint. -// This program should wait until all the spawned threads have finished before exiting. + +// This program spawns multiple threads that each run for at least 250ms, +// and each thread returns how much time they took to complete. +// The program should wait until all the spawned threads have finished and +// should collect their return values into a vector. // I AM NOT DONE use std::thread; -use std::time::Duration; - +use std::time::{Duration, Instant}; fn main() { - let mut handles = vec![]; for i in 0..10 { - thread::spawn(move || { + handles.push(thread::spawn(move || { + let start = Instant::now(); thread::sleep(Duration::from_millis(250)); println!("thread {} is complete", i); - }); + start.elapsed().as_millis() + })); } - let mut completed_threads = 0; + let mut results: Vec<u128> = vec![]; for handle in handles { // TODO: a struct is returned from thread::spawn, can you use it? - completed_threads += 1; } - if completed_threads != 10 { + if results.len() != 10 { panic!("Oh no! All the spawned threads did not finish!"); } + println!(); + for (i, result) in results.into_iter().enumerate() { + println!("thread {} took {}ms", i, result); + } } @@ -969,7 +969,7 @@ A challenge with multi-threaded applications is that the main thread can finish before the spawned threads are completed. https://doc.rust-lang.org/book/ch16-01-threads.html#waiting-for-all-threads-to-finish-using-join-handles -Collect the JoinHandles and wait for them to finish. +Use the JoinHandles to wait for each thread to finish and collect their results. https://doc.rust-lang.org/std/thread/struct.JoinHandle.html """ |