did some more

This commit is contained in:
Stanislav Pankrashin 2022-06-22 16:55:10 +12:00
parent 8239cc2be6
commit b8bedd224f
15 changed files with 70 additions and 64 deletions

View File

@ -1,23 +1,21 @@
// option1.rs // option1.rs
// Make me compile! Execute `rustlings hint option1` for hints // Make me compile! Execute `rustlings hint option1` for hints
// I AM NOT DONE
// you can modify anything EXCEPT for this function's signature // you can modify anything EXCEPT for this function's signature
fn print_number(maybe_number: Option<u16>) { fn print_number(maybe_number: Option<u16>) {
println!("printing: {}", maybe_number.unwrap()); println!("printing: {}", maybe_number.unwrap());
} }
fn main() { fn main() {
print_number(13); print_number(Some(13));
print_number(99); print_number(Some(99));
let mut numbers: [Option<u16>; 5]; let mut numbers: [Option<u16>; 5] = [Some(0); 5];
for iter in 0..5 { for iter in 0..5 {
let number_to_add: u16 = { let number_to_add: u16 = {
((iter * 1235) + 2) / (4 * 16) ((iter * 1235) + 2) / (4 * 16)
}; };
numbers[iter as usize] = number_to_add; numbers[iter as usize] = Some(number_to_add);
} }
} }

View File

@ -1,16 +1,14 @@
// option2.rs // option2.rs
// Make me compile! Execute `rustlings hint option2` for hints // Make me compile! Execute `rustlings hint option2` for hints
// I AM NOT DONE
fn main() { fn main() {
let optional_word = Some(String::from("rustlings")); let optional_word = Some(String::from("rustlings"));
// TODO: Make this an if let statement whose value is "Some" type // TODO: Make this an if let statement whose value is "Some" type
word = optional_word { if let word = optional_word != None {
println!("The word is: {}", word); println!("The word is: {}", word);
} else { } else {
println!("The optional word doesn't contain anything"); println!("The optional word doesn't contain anything");
} };
let mut optional_integers_vec: Vec<Option<i8>> = Vec::new(); let mut optional_integers_vec: Vec<Option<i8>> = Vec::new();
for x in 1..10 { for x in 1..10 {
@ -19,7 +17,7 @@ fn main() {
// TODO: make this a while let statement - remember that vector.pop also adds another layer of Option<T> // TODO: make this a while let statement - remember that vector.pop also adds another layer of Option<T>
// You can stack `Option<T>`'s into while let and if let // You can stack `Option<T>`'s into while let and if let
integer = optional_integers_vec.pop() { while let Some(integer) = optional_integers_vec.pop() {
println!("current value: {}", integer); println!("current value: {:?}", integer);
} }
} }

View File

@ -1,8 +1,6 @@
// option3.rs // option3.rs
// Make me compile! Execute `rustlings hint option3` for hints // Make me compile! Execute `rustlings hint option3` for hints
// I AM NOT DONE
struct Point { struct Point {
x: i32, x: i32,
y: i32, y: i32,
@ -12,7 +10,7 @@ fn main() {
let y: Option<Point> = Some(Point { x: 100, y: 200 }); let y: Option<Point> = Some(Point { x: 100, y: 200 });
match y { match y {
Some(p) => println!("Co-ordinates are {},{} ", p.x, p.y), Some(ref p) => println!("Co-ordinates are {},{} ", p.x, p.y),
_ => println!("no match"), _ => println!("no match"),
} }
y; // Fix without deleting this line. y; // Fix without deleting this line.

View File

@ -7,8 +7,6 @@
// we expect to get when we call `times_two` with a negative number. // we expect to get when we call `times_two` with a negative number.
// No hints, you can do this :) // No hints, you can do this :)
// I AM NOT DONE
pub fn times_two(num: i32) -> i32 { pub fn times_two(num: i32) -> i32 {
num * 2 num * 2
} }
@ -19,12 +17,12 @@ mod tests {
#[test] #[test]
fn returns_twice_of_positive_numbers() { fn returns_twice_of_positive_numbers() {
assert_eq!(times_two(4), ???); assert_eq!(times_two(4), 8);
} }
#[test] #[test]
fn returns_twice_of_negative_numbers() { fn returns_twice_of_negative_numbers() {
// TODO replace unimplemented!() with an assert for `times_two(-4)` // TODO replace unimplemented!() with an assert for `times_two(-4)`
unimplemented!() assert_eq!(times_two(-4), -8);
} }
} }

View File

@ -18,19 +18,17 @@
// where the second TODO comment is. Try not to create any copies of the `numbers` Vec! // where the second TODO comment is. Try not to create any copies of the `numbers` Vec!
// Execute `rustlings hint arc1` for hints :) // Execute `rustlings hint arc1` for hints :)
// I AM NOT DONE
#![forbid(unused_imports)] // Do not change this, (or the next) line. #![forbid(unused_imports)] // Do not change this, (or the next) line.
use std::sync::Arc; use std::sync::Arc;
use std::thread; use std::thread;
fn main() { fn main() {
let numbers: Vec<_> = (0..100u32).collect(); let numbers: Vec<_> = (0..100u32).collect();
let shared_numbers = // TODO let shared_numbers: Arc<Vec<u32>> = Arc::from(numbers);// TODO
let mut joinhandles = Vec::new(); let mut joinhandles = Vec::new();
for offset in 0..8 { for offset in 0..8 {
let child_numbers = // TODO let child_numbers = Arc::clone(&shared_numbers);// TODO
joinhandles.push(thread::spawn(move || { joinhandles.push(thread::spawn(move || {
let sum: u32 = child_numbers.iter().filter(|n| *n % 8 == offset).sum(); let sum: u32 = child_numbers.iter().filter(|n| *n % 8 == offset).sum();
println!("Sum of offset {} is {}", offset, sum); println!("Sum of offset {} is {}", offset, sum);

View File

@ -16,11 +16,9 @@
// //
// Execute `rustlings hint box1` for hints :) // Execute `rustlings hint box1` for hints :)
// I AM NOT DONE
#[derive(PartialEq, Debug)] #[derive(PartialEq, Debug)]
pub enum List { pub enum List {
Cons(i32, List), Cons(i32, Box<List>),
Nil, Nil,
} }
@ -33,11 +31,12 @@ fn main() {
} }
pub fn create_empty_list() -> List { pub fn create_empty_list() -> List {
unimplemented!() List::Nil
} }
pub fn create_non_empty_list() -> List { pub fn create_non_empty_list() -> List {
unimplemented!() use List::Cons;
List::Cons(0, Box::new(Cons(1, Box::new(List::Nil))))
} }
#[cfg(test)] #[cfg(test)]

View File

@ -8,17 +8,15 @@
// //
// Execute `rustlings hint iterators1` for hints :D // 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 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(), 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(), 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(), Some(&"raspberry"));
assert_eq!(my_iterable_fav_fruits.next(), ???); // TODO: Step 4 assert_eq!(my_iterable_fav_fruits.next(), None); // TODO: Step 4
} }

View File

@ -3,8 +3,6 @@
// can offer. Follow the steps to complete the exercise. // can offer. Follow the steps to complete the exercise.
// As always, there are hints if you execute `rustlings hint iterators2`! // As always, there are hints if you execute `rustlings hint iterators2`!
// I AM NOT DONE
// Step 1. // Step 1.
// Complete the `capitalize_first` function. // Complete the `capitalize_first` function.
// "hello" -> "Hello" // "hello" -> "Hello"
@ -12,7 +10,12 @@ pub fn capitalize_first(input: &str) -> String {
let mut c = input.chars(); let mut c = input.chars();
match c.next() { match c.next() {
None => String::new(), None => String::new(),
Some(first) => ???, Some(first) => {
let mut new_string = first.to_uppercase().to_string();
let remaining_str = c.as_str();
new_string.push_str(remaining_str);
new_string
}
} }
} }
@ -21,7 +24,12 @@ pub fn capitalize_first(input: &str) -> String {
// Return a vector of strings. // Return a vector of strings.
// ["hello", "world"] -> ["Hello", "World"] // ["hello", "world"] -> ["Hello", "World"]
pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> { pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> {
vec![] let mut result_vec: Vec<String> = vec![];
for word in words {
result_vec.push(capitalize_first(word));
}
result_vec
} }
// Step 3. // Step 3.
@ -29,7 +37,7 @@ pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> {
// Return a single string. // Return a single string.
// ["hello", " ", "world"] -> "Hello World" // ["hello", " ", "world"] -> "Hello World"
pub fn capitalize_words_string(words: &[&str]) -> String { pub fn capitalize_words_string(words: &[&str]) -> String {
String::new() capitalize_words_vector(words).join("")
} }
#[cfg(test)] #[cfg(test)]

View File

@ -6,8 +6,6 @@
// list_of_results functions. // list_of_results functions.
// Execute `rustlings hint iterators3` to get some hints! // Execute `rustlings hint iterators3` to get some hints!
// I AM NOT DONE
#[derive(Debug, PartialEq, Eq)] #[derive(Debug, PartialEq, Eq)]
pub enum DivisionError { pub enum DivisionError {
NotDivisible(NotDivisibleError), NotDivisible(NotDivisibleError),
@ -22,20 +20,31 @@ pub struct NotDivisibleError {
// Calculate `a` divided by `b` if `a` is evenly divisible by `b`. // Calculate `a` divided by `b` if `a` is evenly divisible by `b`.
// Otherwise, return a suitable error. // Otherwise, 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 {
return Err(DivisionError::DivideByZero)
} else if a % b != 0 {
return Err(DivisionError::NotDivisible(NotDivisibleError {dividend: a, divisor: b}))
}
return Ok(a / b)
}
// Complete the function and return a value of the correct type so the test passes. // Complete the function and return a value of the correct type so the test passes.
// Desired output: Ok([1, 11, 1426, 3]) // Desired output: Ok([1, 11, 1426, 3])
fn result_with_list() -> () { fn result_with_list() -> Result<Vec<i32>, DivisionError> {
let numbers = vec![27, 297, 38502, 81]; let numbers = vec![27, 297, 38502, 81];
let division_results = numbers.into_iter().map(|n| divide(n, 27)); let division_results: Result<Vec<i32>, DivisionError> = numbers.into_iter().map(|n| divide(n, 27)).collect();
division_results
} }
// Complete the function and return a value of the correct type so the test passes. // Complete the function and return a value of the correct type so the test passes.
// Desired output: [Ok(1), Ok(11), Ok(1426), Ok(3)] // Desired output: [Ok(1), Ok(11), Ok(1426), Ok(3)]
fn list_of_results() -> () { fn list_of_results() -> Vec<Result<i32, DivisionError>> {
let numbers = vec![27, 297, 38502, 81]; let numbers = vec![27, 297, 38502, 81];
let division_results = numbers.into_iter().map(|n| divide(n, 27)); let division_results: Vec<Result<i32, DivisionError>> = numbers.into_iter().map(|n| divide(n, 27)).collect();
division_results
} }
#[cfg(test)] #[cfg(test)]

View File

@ -1,7 +1,5 @@
// iterators4.rs // iterators4.rs
// I AM NOT DONE
pub fn factorial(num: u64) -> u64 { pub fn factorial(num: u64) -> u64 {
// Complete this function to return the factorial of num // Complete this function to return the factorial of num
// Do not use: // Do not use:
@ -12,6 +10,10 @@ pub fn factorial(num: u64) -> u64 {
// For an extra challenge, don't use: // For an extra challenge, don't use:
// - recursion // - recursion
// Execute `rustlings hint iterators4` for hints. // Execute `rustlings hint iterators4` for hints.
match (1..num + 1).map(|x| x).reduce(|a, b| a * b) {
Some(result) => result,
None => panic!("something went really wrong"),
}
} }
#[cfg(test)] #[cfg(test)]

View File

@ -6,12 +6,10 @@
// This test has a problem with it -- make the test compile! Make the test // This test has a problem with it -- make the test compile! Make the test
// pass! Make the test fail! Execute `rustlings hint tests1` for hints :) // pass! Make the test fail! Execute `rustlings hint tests1` for hints :)
// I AM NOT DONE
#[cfg(test)] #[cfg(test)]
mod tests { mod tests {
#[test] #[test]
fn you_can_assert() { fn you_can_assert() {
assert!(); assert!(true);
} }
} }

View File

@ -2,12 +2,10 @@
// This test has a problem with it -- make the test compile! Make the test // This test has a problem with it -- make the test compile! Make the test
// pass! Make the test fail! Execute `rustlings hint tests2` for hints :) // pass! Make the test fail! Execute `rustlings hint tests2` for hints :)
// I AM NOT DONE
#[cfg(test)] #[cfg(test)]
mod tests { mod tests {
#[test] #[test]
fn you_can_assert_eq() { fn you_can_assert_eq() {
assert_eq!(); assert_eq!(1, 1);
} }
} }

View File

@ -4,8 +4,6 @@
// we expect to get when we call `is_even(5)`. // we expect to get when we call `is_even(5)`.
// Execute `rustlings hint tests3` for hints :) // Execute `rustlings hint tests3` for hints :)
// I AM NOT DONE
pub fn is_even(num: i32) -> bool { pub fn is_even(num: i32) -> bool {
num % 2 == 0 num % 2 == 0
} }
@ -16,11 +14,11 @@ mod tests {
#[test] #[test]
fn is_true_when_even() { fn is_true_when_even() {
assert!(); assert!(is_even(2));
} }
#[test] #[test]
fn is_false_when_odd() { fn is_false_when_odd() {
assert!(); assert!(is_even(3) == false);
} }
} }

View File

@ -8,14 +8,15 @@
// which appends "Bar" to any object // which appends "Bar" to any object
// implementing this trait. // implementing this trait.
// I AM NOT DONE
trait AppendBar { trait AppendBar {
fn append_bar(self) -> Self; fn append_bar(self) -> Self;
} }
impl AppendBar for String { impl AppendBar for String {
//Add your code here fn append_bar(mut self) -> Self {
self.push_str("Bar");
self
}
} }
fn main() { fn main() {

View File

@ -10,21 +10,26 @@
// No boiler plate code this time, // No boiler plate code this time,
// you can do this! // you can do this!
// I AM NOT DONE
trait AppendBar { trait AppendBar {
fn append_bar(self) -> Self; fn append_bar(self) -> Self;
} }
//TODO: Add your code here //TODO: Add your code here
impl AppendBar for Vec<String> {
fn append_bar(mut self) -> Self {
self.push(String::from("Bar"));
self
}
}
#[cfg(test)] #[cfg(test)]
mod tests { mod tests {
use super::*; use super::*;
#[test] #[test]
fn is_vec_pop_eq_bar() { fn is_vec_pop_eq_bar() {
let mut foo = vec![String::from("Foo")].append_bar(); let mut foo: Vec<String> = vec![String::from("Foo")].append_bar();
assert_eq!(foo.pop().unwrap(), String::from("Bar")); assert_eq!(foo.pop().unwrap(), String::from("Bar"));
assert_eq!(foo.pop().unwrap(), String::from("Foo")); assert_eq!(foo.pop().unwrap(), String::from("Foo"));
} }