feat: complete threads

exercises/threads/threads1.rs

@@ -6,8 +6,6 @@
 // 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, Instant};
 
@@ -24,13 +22,13 @@ fn main() {
 
     let mut results: Vec<u128> = vec![];
     for handle in handles {
-        // TODO: a struct is returned from thread::spawn, can you use it?
+        results.push(handle.join().unwrap());
     }
 
     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);

exercises/threads/threads2.rs

@@ -3,25 +3,27 @@
 // Building on the last exercise, we want all of the threads to complete their work but this time
 // the spawned threads need to be in charge of updating a shared value: JobStatus.jobs_completed
 
-// I AM NOT DONE
-
-use std::sync::Arc;
+use std::sync::{Arc, Mutex};
 use std::thread;
 use std::time::Duration;
 
+#[derive(Debug)]
 struct JobStatus {
     jobs_completed: u32,
 }
 
 fn main() {
-    let status = Arc::new(JobStatus { jobs_completed: 0 });
+    let status = Arc::new(Mutex::new(JobStatus { jobs_completed: 0 }));
     let mut handles = vec![];
     for _ in 0..10 {
         let status_shared = Arc::clone(&status);
         let handle = thread::spawn(move || {
             thread::sleep(Duration::from_millis(250));
             // TODO: You must take an action before you update a shared value
-            status_shared.jobs_completed += 1;
+            match status_shared.lock() {
+                Err(e) => todo!(),
+                Ok(mut status) => status.jobs_completed += 1,
+            }
         });
         handles.push(handle);
     }
@@ -29,6 +31,7 @@ fn main() {
         handle.join().unwrap();
         // TODO: Print the value of the JobStatus.jobs_completed. Did you notice anything
         // interesting in the output? Do you have to 'join' on all the handles?
-        println!("jobs completed {}", ???);
+        let status_shared = Arc::clone(&status);
+        println!("jobs completed {:?}", status_shared.lock().unwrap())
     }
 }

exercises/threads/threads3.rs

@@ -1,8 +1,6 @@
 // threads3.rs
 // Execute `rustlings hint threads3` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 use std::sync::mpsc;
 use std::sync::Arc;
 use std::thread;
@@ -26,13 +24,15 @@ impl Queue {
 
 fn send_tx(q: Queue, tx: mpsc::Sender<u32>) -> () {
     let qc = Arc::new(q);
-    let qc1 = Arc::clone(&qc);
-    let qc2 = Arc::clone(&qc);
+    let qc1 = qc.clone();
+    let qc2 = qc.clone();
+    let tx1 = tx.clone();
+    let tx2 = tx.clone();
 
     thread::spawn(move || {
         for val in &qc1.first_half {
             println!("sending {:?}", val);
-            tx.send(*val).unwrap();
+            tx2.send(*val).unwrap();
             thread::sleep(Duration::from_secs(1));
         }
     });
@@ -40,7 +40,7 @@ fn send_tx(q: Queue, tx: mpsc::Sender<u32>) -> () {
     thread::spawn(move || {
         for val in &qc2.second_half {
             println!("sending {:?}", val);
-            tx.send(*val).unwrap();
+            tx1.send(*val).unwrap();
             thread::sleep(Duration::from_secs(1));
         }
     });