Current Progress: 92/94

exercises/smart_pointers/arc1.rs

@@ -18,7 +18,6 @@
 // where the second TODO comment is. Try not to create any copies of the `numbers` Vec!
 // Execute `rustlings hint arc1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
 
 #![forbid(unused_imports)] // Do not change this, (or the next) line.
 use std::sync::Arc;
@@ -26,11 +25,11 @@ use std::thread;
 
 fn main() {
     let numbers: Vec<_> = (0..100u32).collect();
-    let shared_numbers = // TODO
+    let shared_numbers = Arc::new(numbers);// TODO
     let mut joinhandles = Vec::new();
 
     for offset in 0..8 {
-        let child_numbers = // TODO
+        let child_numbers = shared_numbers.clone();// TODO
         joinhandles.push(thread::spawn(move || {
             let sum: u32 = child_numbers.iter().filter(|&&n| n % 8 == offset).sum();
             println!("Sum of offset {} is {}", offset, sum);

exercises/smart_pointers/box1.rs

@@ -16,11 +16,10 @@
 //
 // Execute `rustlings hint box1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
 
 #[derive(PartialEq, Debug)]
 pub enum List {
-    Cons(i32, List),
+    Cons(i32, Box<List>),
     Nil,
 }
 
@@ -33,11 +32,11 @@ fn main() {
 }
 
 pub fn create_empty_list() -> List {
-    todo!()
+    List::Nil
 }
 
 pub fn create_non_empty_list() -> List {
-    todo!()
+    List::Cons(0, Box::new(List::Nil))
 }
 
 #[cfg(test)]

exercises/smart_pointers/cow1.rs

@@ -8,7 +8,6 @@
 // This exercise is meant to show you what to expect when passing data to Cow.
 // Fix the unit tests by checking for Cow::Owned(_) and Cow::Borrowed(_) at the TODO markers.
 
-// I AM NOT DONE
 
 use std::borrow::Cow;
 
@@ -44,7 +43,8 @@ mod tests {
         let slice = [0, 1, 2];
         let mut input = Cow::from(&slice[..]);
         match abs_all(&mut input) {
-            // TODO
+            Cow::Borrowed(_) => Ok(()),
+            _ => Err("Expected owned value"),
         }
     }
 
@@ -56,7 +56,8 @@ mod tests {
         let slice = vec![0, 1, 2];
         let mut input = Cow::from(slice);
         match abs_all(&mut input) {
-            // TODO
+            Cow::Owned(_) => Ok(()),
+            _ => Err("Expected owned value"),
         }
     }
 
@@ -68,7 +69,8 @@ mod tests {
         let slice = vec![-1, 0, 1];
         let mut input = Cow::from(slice);
         match abs_all(&mut input) {
-            // TODO
+            Cow::Owned(_) => Ok(()),
+            _ => Err("Expected owned value"),
         }
     }
 }

exercises/smart_pointers/rc1.rs

@@ -5,7 +5,6 @@
 
 // Make this code compile by using the proper Rc primitives to express that the sun has multiple owners.
 
-// I AM NOT DONE
 
 use std::rc::Rc;
 
@@ -55,17 +54,17 @@ fn main() {
     jupiter.details();
 
     // TODO
-    let saturn = Planet::Saturn(Rc::new(Sun {}));
+    let saturn = Planet::Saturn(Rc::clone(&sun));
     println!("reference count = {}", Rc::strong_count(&sun)); // 7 references
     saturn.details();
 
     // TODO
-    let uranus = Planet::Uranus(Rc::new(Sun {}));
+    let uranus = Planet::Uranus(Rc::clone(&sun));
     println!("reference count = {}", Rc::strong_count(&sun)); // 8 references
     uranus.details();
 
     // TODO
-    let neptune = Planet::Neptune(Rc::new(Sun {}));
+    let neptune = Planet::Neptune(Rc::clone(&sun));
     println!("reference count = {}", Rc::strong_count(&sun)); // 9 references
     neptune.details();
 
@@ -87,12 +86,15 @@ fn main() {
     println!("reference count = {}", Rc::strong_count(&sun)); // 4 references
 
     // TODO
+    drop(earth);
     println!("reference count = {}", Rc::strong_count(&sun)); // 3 references
 
     // TODO
+    drop(venus);
     println!("reference count = {}", Rc::strong_count(&sun)); // 2 references
 
     // TODO
+    drop(mercury);
     println!("reference count = {}", Rc::strong_count(&sun)); // 1 reference
 
     assert_eq!(Rc::strong_count(&sun), 1);