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Author: road2coder

Diff for: exercises/generics/generics1.rs

@@ -6,9 +6,7 @@
 // Execute `rustlings hint generics1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
-    let mut shopping_list: Vec<?> = Vec::new();
+    let mut shopping_list: Vec<&str> = Vec::new();
     shopping_list.push("milk");
 }

Diff for: exercises/generics/generics2.rs

@@ -6,14 +6,12 @@
 // Execute `rustlings hint generics2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
-struct Wrapper {
-    value: u32,
+struct Wrapper<T> {
+    value: T,
 }
 
-impl Wrapper {
-    pub fn new(value: u32) -> Self {
+impl <T> Wrapper <T> {
+    pub fn new(value: T) -> Self {
         Wrapper { value }
     }
 }

Diff for: exercises/iterators/iterators1.rs

@@ -9,17 +9,15 @@
 // Execute `rustlings hint iterators1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     let my_fav_fruits = vec!["banana", "custard apple", "avocado", "peach", "raspberry"];
 
-    let mut my_iterable_fav_fruits = ???;   // TODO: Step 1
+    let mut my_iterable_fav_fruits = my_fav_fruits.iter();   // TODO: Step 1
 
     assert_eq!(my_iterable_fav_fruits.next(), Some(&"banana"));
-    assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 2
+    assert_eq!(my_iterable_fav_fruits.next(), Some(&"custard apple"));     // TODO: Step 2
     assert_eq!(my_iterable_fav_fruits.next(), Some(&"avocado"));
-    assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 3
+    assert_eq!(my_iterable_fav_fruits.next(), Some(&"peach"));     // TODO: Step 3
     assert_eq!(my_iterable_fav_fruits.next(), Some(&"raspberry"));
-    assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 4
+    assert_eq!(my_iterable_fav_fruits.next(), None);     // TODO: Step 4
 }

Diff for: exercises/iterators/iterators2.rs

@@ -6,16 +6,14 @@
 // Execute `rustlings hint iterators2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 // Step 1.
 // Complete the `capitalize_first` function.
 // "hello" -> "Hello"
 pub fn capitalize_first(input: &str) -> String {
     let mut c = input.chars();
     match c.next() {
         None => String::new(),
-        Some(first) => ???,
+        Some(first) => first.to_uppercase().collect::<String>() + c.as_str(),
     }
 }
 
@@ -24,15 +22,18 @@ pub fn capitalize_first(input: &str) -> String {
 // Return a vector of strings.
 // ["hello", "world"] -> ["Hello", "World"]
 pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> {
-    vec![]
+    words.iter().map(|word| capitalize_first(word)).collect()
 }
 
 // Step 3.
 // Apply the `capitalize_first` function again to a slice of string slices.
 // Return a single string.
 // ["hello", " ", "world"] -> "Hello World"
 pub fn capitalize_words_string(words: &[&str]) -> String {
-    String::new()
+    words
+        .iter()
+        .map(|word| capitalize_first(word))
+        .fold(String::new(), |acc, item| acc + &item)
 }
 
 #[cfg(test)]

Diff for: exercises/lifetimes/lifetimes1.rs

@@ -8,9 +8,7 @@
 // Execute `rustlings hint lifetimes1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
-fn longest(x: &str, y: &str) -> &str {
+fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
     if x.len() > y.len() {
         x
     } else {

Diff for: exercises/lifetimes/lifetimes2.rs

@@ -6,8 +6,6 @@
 // Execute `rustlings hint lifetimes2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
     if x.len() > y.len() {
         x
@@ -22,6 +20,6 @@ fn main() {
     {
         let string2 = String::from("xyz");
         result = longest(string1.as_str(), string2.as_str());
+        println!("The longest string is '{}'", result);
     }
-    println!("The longest string is '{}'", result);
 }

Diff for: exercises/lifetimes/lifetimes3.rs

@@ -5,11 +5,9 @@
 // Execute `rustlings hint lifetimes3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
-struct Book {
-    author: &str,
-    title: &str,
+struct Book<'a> {
+    author: &'a str,
+    title: &'a str,
 }
 
 fn main() {

Diff for: exercises/macros/macros1.rs

@@ -3,14 +3,12 @@
 // Execute `rustlings hint macros1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 macro_rules! my_macro {
     () => {
         println!("Check out my macro!");
     };
 }
 
 fn main() {
-    my_macro();
+    my_macro!();
 }

Diff for: exercises/macros/macros2.rs

@@ -3,14 +3,13 @@
 // Execute `rustlings hint macros2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
-fn main() {
-    my_macro!();
-}
-
 macro_rules! my_macro {
     () => {
         println!("Check out my macro!");
     };
 }
+
+fn main() {
+    my_macro!();
+}
+

Diff for: exercises/options/options1.rs

@@ -3,7 +3,6 @@
 // Execute `rustlings hint options1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 // This function returns how much icecream there is left in the fridge.
 // If it's before 10PM, there's 5 pieces left. At 10PM, someone eats them
@@ -13,7 +12,13 @@ fn maybe_icecream(time_of_day: u16) -> Option<u16> {
     // value of 0 The Option output should gracefully handle cases where
     // time_of_day > 23.
     // TODO: Complete the function body - remember to return an Option!
-    ???
+    if time_of_day > 23 {
+        None
+    } else if time_of_day > 21 {
+        Some(0)
+    } else {
+        Some(5)
+    }
 }
 
 #[cfg(test)]
@@ -34,6 +39,6 @@ mod tests {
         // TODO: Fix this test. How do you get at the value contained in the
         // Option?
         let icecreams = maybe_icecream(12);
-        assert_eq!(icecreams, 5);
+        assert_eq!(icecreams, Some(5));
     }
 }

Diff for: exercises/quiz3.rs

@@ -16,18 +16,20 @@
 //
 // Execute `rustlings hint quiz3` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
+use std::fmt::Display;
 
-pub struct ReportCard {
-    pub grade: f32,
+pub struct ReportCard<T> {
+    pub grade: T,
     pub student_name: String,
     pub student_age: u8,
 }
 
-impl ReportCard {
+impl<T: Display> ReportCard<T> {
     pub fn print(&self) -> String {
-        format!("{} ({}) - achieved a grade of {}",
-            &self.student_name, &self.student_age, &self.grade)
+        format!(
+            "{} ({}) - achieved a grade of {}",
+            &self.student_name, &self.student_age, &self.grade
+        )
     }
 }
 
@@ -50,9 +52,8 @@ mod tests {
 
     #[test]
     fn generate_alphabetic_report_card() {
-        // TODO: Make sure to change the grade here after you finish the exercise.
         let report_card = ReportCard {
-            grade: 2.1,
+            grade: "A+",
             student_name: "Gary Plotter".to_string(),
             student_age: 11,
         };

Diff for: exercises/smart_pointers/arc1.rs

@@ -21,19 +21,17 @@
 //
 // 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;
 use std::thread;
 
 fn main() {
     let numbers: Vec<_> = (0..100u32).collect();
-    let shared_numbers = // TODO
+    let shared_numbers = Arc::new(numbers);
     let mut joinhandles = Vec::new();
 
     for offset in 0..8 {
-        let child_numbers = // TODO
+        let child_numbers = Arc::clone(&shared_numbers);
         joinhandles.push(thread::spawn(move || {
             let sum: u32 = child_numbers.iter().filter(|&&n| n % 8 == offset).sum();
             println!("Sum of offset {} is {}", offset, sum);

Diff for: exercises/smart_pointers/box1.rs

@@ -18,11 +18,9 @@
 //
 // 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,
 }
 
@@ -35,11 +33,11 @@ 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)]

Diff for: exercises/smart_pointers/cow1.rs

@@ -12,8 +12,6 @@
 //
 // Execute `rustlings hint cow1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 use std::borrow::Cow;
 
 fn abs_all<'a, 'b>(input: &'a mut Cow<'b, [i32]>) -> &'a mut Cow<'b, [i32]> {
@@ -48,7 +46,8 @@ mod tests {
         let slice = [0, 1, 2];
         let mut input = Cow::from(&slice[..]);
         match abs_all(&mut input) {
-            // TODO
+            Cow::Borrowed(_) => Ok(()),
+            _ => Err("Expected Borrowed value"),
         }
     }
 
@@ -60,7 +59,8 @@ 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"),
         }
     }
 
@@ -72,7 +72,8 @@ mod tests {
         let slice = vec![-1, 0, 1];
         let mut input = Cow::from(slice);
         match abs_all(&mut input) {
-            // TODO
+            Cow::Owned(_) => Ok(()),
+            _ => Err("Clone occurred"),
         }
     }
 }

Diff for: exercises/smart_pointers/rc1.rs

@@ -10,8 +10,6 @@
 //
 // Execute `rustlings hint rc1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 use std::rc::Rc;
 
 #[derive(Debug)]
@@ -59,18 +57,16 @@ fn main() {
     println!("reference count = {}", Rc::strong_count(&sun)); // 6 references
     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();
 
@@ -91,13 +87,13 @@ fn main() {
     drop(mars);
     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);

Diff for: exercises/traits/traits3.rs

@@ -8,10 +8,10 @@
 // Execute `rustlings hint traits3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 pub trait Licensed {
-    fn licensing_info(&self) -> String;
+    fn licensing_info(&self) -> String {
+        String::from("Some information")
+    }
 }
 
 struct SomeSoftware {

Diff for: exercises/traits/traits4.rs

@@ -7,7 +7,6 @@
 // Execute `rustlings hint traits4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 pub trait Licensed {
     fn licensing_info(&self) -> String {
@@ -23,7 +22,7 @@ impl Licensed for SomeSoftware {}
 impl Licensed for OtherSoftware {}
 
 // YOU MAY ONLY CHANGE THE NEXT LINE
-fn compare_license_types(software: ??, software_two: ??) -> bool {
+fn compare_license_types(software: impl Licensed, software_two: impl Licensed) -> bool {
     software.licensing_info() == software_two.licensing_info()
 }