From cc8e0bc00a2b6eb9fc8f9f398c0979bed352dbca Mon Sep 17 00:00:00 2001
From: David Bailey <davidbailey00@outlook.com>
Date: Sat, 16 Jan 2021 20:45:36 +0000
Subject: [PATCH] Add standard_library_types solutions
---
exercises/standard_library_types/arc1.rs | 5 ++---
exercises/standard_library_types/box1.rs | 8 +++----
.../standard_library_types/iterators1.rs | 18 +++++++--------
.../standard_library_types/iterators2.rs | 9 ++++----
.../standard_library_types/iterators3.rs | 22 ++++++++++++-------
.../standard_library_types/iterators4.rs | 3 +--
6 files changed, 32 insertions(+), 33 deletions(-)
diff --git a/exercises/standard_library_types/arc1.rs b/exercises/standard_library_types/arc1.rs
index 4ad649f..27e1c8f 100644
--- a/exercises/standard_library_types/arc1.rs
+++ b/exercises/standard_library_types/arc1.rs
@@ -4,18 +4,17 @@
// somewhere. Try not to create any copies of the `numbers` Vec!
// Execute `rustlings hint arc1` for hints :)
-// 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 = Arc::clone(&shared_numbers);
joinhandles.push(thread::spawn(move || {
let mut i = offset;
let mut sum = 0;
diff --git a/exercises/standard_library_types/box1.rs b/exercises/standard_library_types/box1.rs
index f312f3d..a138bf4 100644
--- a/exercises/standard_library_types/box1.rs
+++ b/exercises/standard_library_types/box1.rs
@@ -16,11 +16,9 @@
//
// Execute `rustlings hint box1` for hints :)
-// I AM NOT DONE
-
#[derive(PartialEq, Debug)]
pub enum List {
- Cons(i32, List),
+ Cons(String, Box<List>),
Nil,
}
@@ -33,11 +31,11 @@ fn main() {
}
pub fn create_empty_list() -> List {
- unimplemented!()
+ List::Nil
}
pub fn create_non_empty_list() -> List {
- unimplemented!()
+ List::Cons(String::from("hello"), Box::new(List::Nil))
}
#[cfg(test)]
diff --git a/exercises/standard_library_types/iterators1.rs b/exercises/standard_library_types/iterators1.rs
index 3fd519d..f98f5c6 100644
--- a/exercises/standard_library_types/iterators1.rs
+++ b/exercises/standard_library_types/iterators1.rs
@@ -1,24 +1,22 @@
// iterators1.rs
-//
+//
// Make me compile by filling in the `???`s
//
// When performing operations on elements within a collection, iterators are essential.
-// This module helps you get familiar with the structure of using an iterator and
+// This module helps you get familiar with the structure of using an iterator and
// how to go through elements within an iterable collection.
-//
+//
// Execute `rustlings hint iterators1` for hints :D
-// I AM NOT DONE
-
-fn main () {
+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();
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"));
assert_eq!(my_iterable_fav_fruits.next(), Some(&"avocado"));
- assert_eq!(my_iterable_fav_fruits.next(), ???); // TODO: Step 2.1
+ assert_eq!(my_iterable_fav_fruits.next(), Some(&"peach"));
assert_eq!(my_iterable_fav_fruits.next(), Some(&"raspberry"));
- assert_eq!(my_iterable_fav_fruits.next(), ???); // TODO: Step 3
+ assert_eq!(my_iterable_fav_fruits.next(), None);
}
diff --git a/exercises/standard_library_types/iterators2.rs b/exercises/standard_library_types/iterators2.rs
index 84d14ae..daacdc4 100644
--- a/exercises/standard_library_types/iterators2.rs
+++ b/exercises/standard_library_types/iterators2.rs
@@ -7,13 +7,11 @@
// Try to ensure it returns a single string.
// As always, there are hints if you execute `rustlings hint iterators2`!
-// I AM NOT DONE
-
pub fn capitalize_first(input: &str) -> String {
let mut c = input.chars();
match c.next() {
None => String::new(),
- Some(first) => first.collect::<String>() + c.as_str(),
+ Some(first) => first.to_uppercase().collect::<String>() + c.as_str(),
}
}
@@ -37,14 +35,15 @@ mod tests {
#[test]
fn test_iterate_string_vec() {
let words = vec!["hello", "world"];
- let capitalized_words: Vec<String> = // TODO
+ let capitalized_words: Vec<String> =
+ words.iter().map(|word| capitalize_first(word)).collect();
assert_eq!(capitalized_words, ["Hello", "World"]);
}
#[test]
fn test_iterate_into_string() {
let words = vec!["hello", " ", "world"];
- let capitalized_words = // TODO
+ let capitalized_words: String = words.iter().map(|word| capitalize_first(word)).collect();
assert_eq!(capitalized_words, "Hello World");
}
}
diff --git a/exercises/standard_library_types/iterators3.rs b/exercises/standard_library_types/iterators3.rs
index 353cea6..7deabf6 100644
--- a/exercises/standard_library_types/iterators3.rs
+++ b/exercises/standard_library_types/iterators3.rs
@@ -7,8 +7,6 @@
// Execute `rustlings hint iterators3` to get some hints!
// Have fun :-)
-// I AM NOT DONE
-
#[derive(Debug, PartialEq, Eq)]
pub enum DivisionError {
NotDivisible(NotDivisibleError),
@@ -24,7 +22,18 @@ pub struct NotDivisibleError {
// This function should calculate `a` divided by `b` if `a` is
// evenly divisible by b.
// Otherwise, it should return a suitable error.
-pub fn divide(a: i32, b: i32) -> Result<i32, DivisionError> {}
+pub fn divide(a: i32, b: i32) -> Result<i32, DivisionError> {
+ if b == 0 {
+ Err(DivisionError::DivideByZero)
+ } else if a % b == 0 {
+ Ok(a / b)
+ } else {
+ Err(DivisionError::NotDivisible(NotDivisibleError {
+ dividend: a,
+ divisor: b,
+ }))
+ }
+}
#[cfg(test)]
mod tests {
@@ -57,13 +66,11 @@ mod tests {
assert_eq!(divide(0, 81), Ok(0));
}
- // Iterator exercises using your `divide` function
- /*
#[test]
fn result_with_list() {
let numbers = vec![27, 297, 38502, 81];
let division_results = numbers.into_iter().map(|n| divide(n, 27));
- let x //... Fill in here!
+ let x: Result<Vec<_>, _> = division_results.collect();
assert_eq!(format!("{:?}", x), "Ok([1, 11, 1426, 3])");
}
@@ -71,8 +78,7 @@ mod tests {
fn list_of_results() {
let numbers = vec![27, 297, 38502, 81];
let division_results = numbers.into_iter().map(|n| divide(n, 27));
- let x //... Fill in here!
+ let x: Vec<_> = division_results.collect();
assert_eq!(format!("{:?}", x), "[Ok(1), Ok(11), Ok(1426), Ok(3)]");
}
- */
}
diff --git a/exercises/standard_library_types/iterators4.rs b/exercises/standard_library_types/iterators4.rs
index 8886283..1ba25ac 100644
--- a/exercises/standard_library_types/iterators4.rs
+++ b/exercises/standard_library_types/iterators4.rs
@@ -1,7 +1,5 @@
// iterators4.rs
-// I AM NOT DONE
-
pub fn factorial(num: u64) -> u64 {
// Complete this function to return the factorial of num
// Do not use:
@@ -12,6 +10,7 @@ pub fn factorial(num: u64) -> u64 {
// For an extra challenge, don't use:
// - recursion
// Execute `rustlings hint iterators4` for hints.
+ (1..=num).product()
}
#[cfg(test)]