completed

This commit is contained in:
Bruce 2023-03-29 02:17:15 +08:00
parent 4e37057ba9
commit ea6f103729
72 changed files with 239 additions and 285 deletions

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@ -6,12 +6,10 @@
// check clippy's suggestions from the output to solve the exercise.
// Execute `rustlings hint clippy1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
use std::f32;
fn main() {
let pi = 3.14f32;
let pi = f32::consts::PI;
let radius = 5.00f32;
let area = pi * f32::powi(radius, 2);

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@ -1,12 +1,10 @@
// clippy2.rs
// Execute `rustlings hint clippy2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let mut res = 42;
let option = Some(12);
for x in option {
if let Some(x) = option {
res += x;
}
println!("{}", res);

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@ -1,28 +1,25 @@
// clippy3.rs
// Here's a couple more easy Clippy fixes, so you can see its utility.
// I AM NOT DONE
#[allow(unused_variables, unused_assignments)]
fn main() {
let my_option: Option<()> = None;
if my_option.is_none() {
if let Some(p) = my_option {
my_option.unwrap();
}
let my_arr = &[
-1, -2, -3
-1, -2, -3,
-4, -5, -6
];
println!("My array! Here it is: {:?}", my_arr);
let my_empty_vec = vec![1, 2, 3, 4, 5].resize(0, 5);
let my_empty_vec = vec![0;5];
println!("This Vec is empty, see? {:?}", my_empty_vec);
let mut value_a = 45;
let mut value_b = 66;
// Let's swap these two!
value_a = value_b;
value_b = value_a;
std::mem::swap(&mut value_a, &mut value_b);
println!("value a: {}; value b: {}", value_a, value_b);
}

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@ -1,11 +1,13 @@
// enums1.rs
// No hints this time! ;)
// I AM NOT DONE
#[derive(Debug)]
enum Message {
// TODO: define a few types of messages as used below
Quit,
Echo,
Move,
ChangeColor
}
fn main() {

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@ -1,11 +1,13 @@
// enums2.rs
// Execute `rustlings hint enums2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[derive(Debug)]
enum Message {
// TODO: define the different variants used below
Move { x: i32, y: i32 },
Echo(String),
ChangeColor(u8, u8, u8),
Quit,
}
impl Message {

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@ -2,10 +2,12 @@
// Address all the TODOs to make the tests pass!
// Execute `rustlings hint enums3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
enum Message {
// TODO: implement the message variant types based on their usage below
Move(Point),
Echo(String),
ChangeColor(u8, u8, u8),
Quit,
}
struct Point {
@ -39,6 +41,12 @@ impl State {
fn process(&mut self, message: Message) {
// TODO: create a match expression to process the different message variants
// Remember: When passing a tuple as a function argument, you'll need extra parentheses: fn function((t, u, p, l, e))
match message {
Message::Quit => self.quit(),
Message::Echo(s) => self.echo(s),
Message::Move(p) => self.move_position(p),
Message::ChangeColor(r, g, b) => self.change_color((r,g,b))
}
}
}

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@ -5,14 +5,12 @@
// construct to `Option` that can be used to express error conditions. Let's use it!
// Execute `rustlings hint errors1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
pub fn generate_nametag_text(name: String) -> Option<String> {
pub fn generate_nametag_text(name: String) -> Result<String, String> {
if name.is_empty() {
// Empty names aren't allowed.
None
Err("`name` was empty; it must be nonempty.".to_string())
} else {
Some(format!("Hi! My name is {}", name))
Ok(format!("Hi! My name is {}", name))
}
}

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@ -17,14 +17,12 @@
// one is a lot shorter!
// Execute `rustlings hint errors2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
use std::num::ParseIntError;
pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
let processing_fee = 1;
let cost_per_item = 5;
let qty = item_quantity.parse::<i32>();
let qty = item_quantity.parse::<i32>()?;
Ok(qty * cost_per_item + processing_fee)
}

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@ -4,21 +4,19 @@
// Why not? What should we do to fix it?
// Execute `rustlings hint errors3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
use std::num::ParseIntError;
fn main() {
let mut tokens = 100;
let pretend_user_input = "8";
let cost = total_cost(pretend_user_input)?;
if cost > tokens {
println!("You can't afford that many!");
} else {
tokens -= cost;
println!("You now have {} tokens.", tokens);
if let Ok(cost) = total_cost(pretend_user_input) {
if cost > tokens {
println!("You can't afford that many!");
} else {
tokens -= cost;
println!("You now have {} tokens.", tokens);
}
}
}

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@ -1,8 +1,6 @@
// errors4.rs
// Execute `rustlings hint errors4` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[derive(PartialEq, Debug)]
struct PositiveNonzeroInteger(u64);
@ -15,7 +13,11 @@ enum CreationError {
impl PositiveNonzeroInteger {
fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> {
// Hmm...? Why is this only returning an Ok value?
Ok(PositiveNonzeroInteger(value as u64))
match value {
v if v < 0 => Err(CreationError::Negative),
v if v == 0 => Err(CreationError::Zero),
_ => Ok(PositiveNonzeroInteger(value as u64)),
}
}
}

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@ -16,14 +16,12 @@
// Execute `rustlings hint errors5` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
use std::error;
use std::fmt;
use std::num::ParseIntError;
// TODO: update the return type of `main()` to make this compile.
fn main() -> Result<(), Box<dyn ???>> {
fn main() -> Result<(), Box<dyn std::error::Error>> {
let pretend_user_input = "42";
let x: i64 = pretend_user_input.parse()?;
println!("output={:?}", PositiveNonzeroInteger::new(x)?);

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@ -8,8 +8,6 @@
// Execute `rustlings hint errors6` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
use std::num::ParseIntError;
// This is a custom error type that we will be using in `parse_pos_nonzero()`.
@ -24,14 +22,19 @@ impl ParsePosNonzeroError {
ParsePosNonzeroError::Creation(err)
}
// TODO: add another error conversion function here.
// fn from_parseint...
fn from_parseint(err: ParseIntError) -> ParsePosNonzeroError {
ParsePosNonzeroError::ParseInt(err)
}
}
fn parse_pos_nonzero(s: &str) -> Result<PositiveNonzeroInteger, ParsePosNonzeroError> {
// TODO: change this to return an appropriate error instead of panicking
// when `parse()` returns an error.
let x: i64 = s.parse().unwrap();
PositiveNonzeroInteger::new(x).map_err(ParsePosNonzeroError::from_creation)
let x = s.parse();
if let Err(e) = x {
return Err(ParsePosNonzeroError::from_parseint(e))
}
PositiveNonzeroInteger::new(x.unwrap()).map_err(ParsePosNonzeroError::from_creation)
}
// Don't change anything below this line.

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@ -1,8 +1,10 @@
// functions1.rs
// Execute `rustlings hint functions1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
call_me();
}
fn call_me() {
println!("why do you call me?");
}

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@ -1,13 +1,11 @@
// functions2.rs
// Execute `rustlings hint functions2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
call_me(3);
}
fn call_me(num:) {
fn call_me(num: i32) {
for i in 0..num {
println!("Ring! Call number {}", i + 1);
}

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@ -1,10 +1,8 @@
// functions3.rs
// Execute `rustlings hint functions3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
call_me();
call_me(4);
}
fn call_me(num: u32) {

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@ -7,14 +7,12 @@
// in the signatures for now. If anything, this is a good way to peek ahead
// to future exercises!)
// I AM NOT DONE
fn main() {
let original_price = 51;
println!("Your sale price is {}", sale_price(original_price));
}
fn sale_price(price: i32) -> {
fn sale_price(price: i32) -> i32 {
if is_even(price) {
price - 10
} else {

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@ -1,13 +1,11 @@
// functions5.rs
// Execute `rustlings hint functions5` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let answer = square(3);
println!("The square of 3 is {}", answer);
}
fn square(num: i32) -> i32 {
num * num;
num * num
}

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@ -3,9 +3,7 @@
// 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<_> = Vec::new();
shopping_list.push("milk");
}

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@ -3,14 +3,12 @@
// 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 }
}
}

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@ -10,18 +10,17 @@
//
// Execute `rustlings hint hashmaps1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
use std::collections::HashMap;
fn fruit_basket() -> HashMap<String, u32> {
let mut basket = // TODO: declare your hash map here.
let mut basket = HashMap::new(); // TODO: declare your hash map here.
// Two bananas are already given for you :)
basket.insert(String::from("banana"), 2);
// TODO: Put more fruits in your basket here.
basket.insert(String::from("apple"), 5);
basket.insert(String::from("peach"), 3);
basket
}

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@ -11,8 +11,6 @@
//
// Execute `rustlings hint hashmaps2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
use std::collections::HashMap;
#[derive(Hash, PartialEq, Eq)]
@ -37,6 +35,9 @@ fn fruit_basket(basket: &mut HashMap<Fruit, u32>) {
// TODO: Put new fruits if not already present. Note that you
// are not allowed to put any type of fruit that's already
// present!
if let None = basket.get(&fruit) {
basket.insert(fruit, 1);
}
}
}

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@ -14,8 +14,6 @@
// Execute `rustlings hint hashmaps3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
use std::collections::HashMap;
// A structure to store team name and its goal details.
@ -40,6 +38,22 @@ fn build_scores_table(results: String) -> HashMap<String, Team> {
// will be the number of goals conceded from team_2, and similarly
// goals scored by team_2 will be the number of goals conceded by
// team_1.
scores.entry(team_1_name.clone()).and_modify(|t| {
t.goals_scored += team_1_score;
t.goals_conceded += team_2_score
}).or_insert(Team {
name: team_1_name,
goals_scored: team_1_score,
goals_conceded: team_2_score
});
scores.entry(team_2_name.clone()).and_modify(|t| {
t.goals_scored += team_2_score;
t.goals_conceded += team_1_score
}).or_insert(Team {
name: team_2_name,
goals_scored: team_2_score,
goals_conceded: team_1_score
});
}
scores
}

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@ -1,13 +1,14 @@
// if1.rs
// Execute `rustlings hint if1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
pub fn bigger(a: i32, b: i32) -> i32 {
// Complete this function to return the bigger number!
// Do not use:
// - another function call
// - additional variables
if a < b {
b
} else {
a
}
}
// Don't mind this for now :)

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@ -4,13 +4,13 @@
// Step 2: Get the bar_for_fuzz and default_to_baz tests passing!
// Execute `rustlings hint if2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
pub fn foo_if_fizz(fizzish: &str) -> &str {
if fizzish == "fizz" {
"foo"
} else if fizzish == "fuzz" {
"bar"
} else {
1
"baz"
}
}

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@ -9,8 +9,6 @@
// when you change one of the lines below! Try adding a `println!` line, or try changing
// what it outputs in your terminal. Try removing a semicolon and see what happens!
// I AM NOT DONE
fn main() {
println!("Hello and");
println!(r#" welcome to... "#);

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@ -2,8 +2,6 @@
// Make the code print a greeting to the world.
// Execute `rustlings hint intro2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
println!("Hello {}!");
println!("Hello {}!", "Bruce");
}

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@ -8,17 +8,15 @@
//
// 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
}

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@ -3,17 +3,16 @@
// can offer. Follow the steps to complete the exercise.
// 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() {
let h = match c.next() {
None => String::new(),
Some(first) => ???,
}
Some(first) => first.to_uppercase().to_string(),
};
h + c.as_str()
}
// Step 2.
@ -21,7 +20,7 @@ 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(|w| capitalize_first(*w)).collect()
}
// Step 3.
@ -29,7 +28,9 @@ pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> {
// Return a single string.
// ["hello", " ", "world"] -> "Hello World"
pub fn capitalize_words_string(words: &[&str]) -> String {
String::new()
words
.iter()
.fold("".to_string(), |acc, s| acc.to_string() + &capitalize_first(s))
}
#[cfg(test)]

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@ -6,8 +6,6 @@
// list_of_results functions.
// Execute `rustlings hint iterators3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[derive(Debug, PartialEq, Eq)]
pub enum DivisionError {
NotDivisible(NotDivisibleError),
@ -20,24 +18,39 @@ pub struct NotDivisibleError {
divisor: i32,
}
use DivisionError::*;
type DivResult = Result<i32, DivisionError>;
// Calculate `a` divided by `b` if `a` is evenly divisible by `b`.
// Otherwise, return a suitable error.
pub fn divide(a: i32, b: i32) -> Result<i32, DivisionError> {
todo!();
if b == 0 {
return Err(DivideByZero)
}
if a == 0 {
return Ok(0)
}
// divisible or not
if a % b == 0 {
return Ok(a/b)
}
Err(NotDivisible(NotDivisibleError { dividend: a, divisor: b}))
}
// Complete the function and return a value of the correct type so the test passes.
// 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 division_results = numbers.into_iter().map(|n| divide(n, 27));
Ok(numbers.into_iter().map(|n| divide(n, 27)).map(|r| r.unwrap()).collect())
}
// 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)]
fn list_of_results() -> () {
fn list_of_results() -> Vec<DivResult> {
let numbers = vec![27, 297, 38502, 81];
let division_results = numbers.into_iter().map(|n| divide(n, 27));
numbers.into_iter().map(|n| divide(n, 27)).collect()
}
#[cfg(test)]

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@ -1,8 +1,6 @@
// iterators4.rs
// Execute `rustlings hint iterators4` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
pub fn factorial(num: u64) -> u64 {
// Complete this function to return the factorial of num
// Do not use:
@ -13,6 +11,8 @@ pub fn factorial(num: u64) -> u64 {
// For an extra challenge, don't use:
// - recursion
// Execute `rustlings hint iterators4` for hints.
(1..=num).product()
// (1..=num).fold(1, |a, b| a * b)
}
#[cfg(test)]

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@ -10,8 +10,6 @@
//
// Make the code compile and the tests pass.
// I AM NOT DONE
use std::collections::HashMap;
#[derive(Clone, Copy, PartialEq, Eq)]
@ -34,7 +32,7 @@ fn count_for(map: &HashMap<String, Progress>, value: Progress) -> usize {
fn count_iterator(map: &HashMap<String, Progress>, value: Progress) -> usize {
// map is a hashmap with String keys and Progress values.
// map = { "variables1": Complete, "from_str": None, ... }
todo!();
map.values().filter(|v| **v != value).count()
}
fn count_collection_for(collection: &[HashMap<String, Progress>], value: Progress) -> usize {
@ -53,7 +51,11 @@ fn count_collection_iterator(collection: &[HashMap<String, Progress>], value: Pr
// collection is a slice of hashmaps.
// collection = [{ "variables1": Complete, "from_str": None, ... },
// { "variables2": Complete, ... }, ... ]
todo!();
let mut cnt = 0;
collection.iter().for_each(|h| {
cnt += h.values().filter(|v| **v == value).count();
});
cnt
}
#[cfg(test)]

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@ -1,8 +1,6 @@
// macros1.rs
// 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!");
@ -10,5 +8,5 @@ macro_rules! my_macro {
}
fn main() {
my_macro();
my_macro!();
}

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@ -1,12 +1,11 @@
// macros2.rs
// Execute `rustlings hint macros2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
my_macro!();
}
#[macro_export]
macro_rules! my_macro {
() => {
println!("Check out my macro!");

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@ -2,9 +2,8 @@
// Make me compile, without taking the macro out of the module!
// Execute `rustlings hint macros3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
mod macros {
#[macro_export]
macro_rules! my_macro {
() => {
println!("Check out my macro!");

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@ -1,13 +1,11 @@
// macros4.rs
// Execute `rustlings hint macros4` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[rustfmt::skip]
macro_rules! my_macro {
() => {
println!("Check out my macro!");
}
};
($val:expr) => {
println!("Look at this other macro: {}", $val);
}

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@ -1,15 +1,13 @@
// modules1.rs
// Execute `rustlings hint modules1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
mod sausage_factory {
// Don't let anybody outside of this module see this!
fn get_secret_recipe() -> String {
String::from("Ginger")
}
fn make_sausage() {
pub fn make_sausage() {
get_secret_recipe();
println!("sausage!");
}

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@ -3,12 +3,10 @@
// 'use' and 'as' keywords. Fix these 'use' statements to make the code compile.
// Execute `rustlings hint modules2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
mod delicious_snacks {
// TODO: Fix these use statements
use self::fruits::PEAR as ???
use self::veggies::CUCUMBER as ???
pub use self::fruits::PEAR as fruit;
pub use self::veggies::CUCUMBER as veggie;
mod fruits {
pub const PEAR: &'static str = "Pear";

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@ -5,10 +5,8 @@
// from the std::time module. Bonus style points if you can do it with one line!
// Execute `rustlings hint modules3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
// TODO: Complete this use statement
use ???
use std::time::{SystemTime, UNIX_EPOCH};
fn main() {
match SystemTime::now().duration_since(UNIX_EPOCH) {

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@ -1,12 +1,10 @@
// move_semantics1.rs
// Execute `rustlings hint move_semantics1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let vec0 = Vec::new();
let vec1 = fill_vec(vec0);
let mut vec1 = fill_vec(vec0);
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);

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@ -2,12 +2,10 @@
// Make me compile without changing line 13 or moving line 10!
// Execute `rustlings hint move_semantics2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let vec0 = Vec::new();
let mut vec1 = fill_vec(vec0);
let mut vec1 = fill_vec(&vec0);
// Do not change the following line!
println!("{} has length {} content `{:?}`", "vec0", vec0.len(), vec0);
@ -17,8 +15,8 @@ fn main() {
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
}
fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
let mut vec = vec;
fn fill_vec(vec: &Vec<i32>) -> Vec<i32> {
let mut vec = vec.clone();
vec.push(22);
vec.push(44);

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@ -3,8 +3,6 @@
// (no lines with multiple semicolons necessary!)
// Execute `rustlings hint move_semantics3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let vec0 = Vec::new();
@ -17,7 +15,7 @@ fn main() {
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
}
fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
fn fill_vec(mut vec: Vec<i32>) -> Vec<i32> {
vec.push(22);
vec.push(44);
vec.push(66);

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@ -4,12 +4,8 @@
// function.
// Execute `rustlings hint move_semantics4` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let vec0 = Vec::new();
let mut vec1 = fill_vec(vec0);
let mut vec1 = fill_vec();
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
@ -20,7 +16,7 @@ fn main() {
// `fill_vec()` no longer takes `vec: Vec<i32>` as argument
fn fill_vec() -> Vec<i32> {
let mut vec = vec;
let mut vec = vec![];
vec.push(22);
vec.push(44);

View File

@ -3,13 +3,11 @@
// adding, changing or removing any of them.
// Execute `rustlings hint move_semantics5` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let mut x = 100;
let y = &mut x;
let z = &mut x;
*y += 100;
let z = &mut x;
*z += 1000;
assert_eq!(x, 1200);
}

View File

@ -2,24 +2,20 @@
// Execute `rustlings hint move_semantics6` or use the `hint` watch subcommand for a hint.
// You can't change anything except adding or removing references.
// I AM NOT DONE
fn main() {
let data = "Rust is great!".to_string();
get_char(data);
get_char(&data);
string_uppercase(&data);
string_uppercase(data);
}
// Should not take ownership
fn get_char(data: String) -> char {
fn get_char(data: &String) -> char {
data.chars().last().unwrap()
}
// Should take ownership
fn string_uppercase(mut data: &String) {
data = &data.to_uppercase();
fn string_uppercase(mut data: String) {
data = data.to_uppercase();
println!("{}", data);
}

View File

@ -1,8 +1,6 @@
// options1.rs
// 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
// all, so there'll be no more left :(
@ -10,7 +8,11 @@ fn maybe_icecream(time_of_day: u16) -> Option<u16> {
// We use the 24-hour system here, so 10PM is a value of 22 and 12AM is a 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!
???
match time_of_day {
t if t < 22 => Some(5),
22..=24 => Some(0),
_ => None
}
}
#[cfg(test)]
@ -30,6 +32,6 @@ mod tests {
fn raw_value() {
// 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));
}
}

View File

@ -1,8 +1,6 @@
// options2.rs
// Execute `rustlings hint options2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[cfg(test)]
mod tests {
#[test]
@ -11,7 +9,7 @@ mod tests {
let optional_target = Some(target);
// TODO: Make this an if let statement whose value is "Some" type
word = optional_target {
if let Some(word) = optional_target {
assert_eq!(word, target);
}
}
@ -26,8 +24,8 @@ mod tests {
// 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
integer = optional_integers.pop() {
assert_eq!(integer, range);
while let Some(integer) = optional_integers.pop() {
assert_eq!(integer, Some(range));
range -= 1;
}
}

View File

@ -1,8 +1,6 @@
// options3.rs
// Execute `rustlings hint options3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
struct Point {
x: i32,
y: i32,
@ -12,7 +10,7 @@ fn main() {
let y: Option<Point> = Some(Point { x: 100, y: 200 });
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"),
}
y; // Fix without deleting this line.

View File

@ -18,19 +18,17 @@
// 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;
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 = shared_numbers.clone();
joinhandles.push(thread::spawn(move || {
let sum: u32 = child_numbers.iter().filter(|&&n| n % 8 == offset).sum();
println!("Sum of offset {} is {}", offset, sum);

View File

@ -16,11 +16,9 @@
//
// 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,
}
@ -33,11 +31,11 @@ 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)]

View File

@ -8,8 +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;
fn abs_all<'a, 'b>(input: &'a mut Cow<'b, [i32]>) -> &'a mut Cow<'b, [i32]> {
@ -44,7 +42,8 @@ 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")
}
}
@ -56,7 +55,8 @@ mod tests {
let slice = vec![0, 1, 2];
let mut input = Cow::from(slice);
match abs_all(&mut input) {
// TODO
Cow::Owned(_) => Ok(()),
_ => Err("need owned value")
}
}
@ -68,7 +68,8 @@ mod tests {
let slice = vec![-1, 0, 1];
let mut input = Cow::from(slice);
match abs_all(&mut input) {
// TODO
Cow::Owned(_) => Ok(()),
_ => Err("should also be owned")
}
}
}

View File

@ -5,8 +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;
#[derive(Debug)]
@ -54,18 +52,15 @@ 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();
@ -86,13 +81,13 @@ 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);

View File

@ -2,13 +2,11 @@
// Make me compile without changing the function signature!
// Execute `rustlings hint strings1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let answer = current_favorite_color();
println!("My current favorite color is {}", answer);
}
fn current_favorite_color() -> String {
"blue"
"blue".to_string()
}

View File

@ -2,11 +2,9 @@
// Make me compile without changing the function signature!
// Execute `rustlings hint strings2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let word = String::from("green"); // Try not changing this line :)
if is_a_color_word(word) {
if is_a_color_word(&word) {
println!("That is a color word I know!");
} else {
println!("That is not a color word I know.");

View File

@ -1,21 +1,19 @@
// strings3.rs
// Execute `rustlings hint strings3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn trim_me(input: &str) -> String {
// TODO: Remove whitespace from both ends of a string!
???
input.trim().to_string()
}
fn compose_me(input: &str) -> String {
// TODO: Add " world!" to the string! There's multiple ways to do this!
???
input.to_string() + " world!"
}
fn replace_me(input: &str) -> String {
// TODO: Replace "cars" in the string with "balloons"!
???
input.replace("cars", "balloons")
}
#[cfg(test)]

View File

@ -6,8 +6,6 @@
// before the parentheses on each line. If you're right, it will compile!
// No hints this time!
// I AM NOT DONE
fn string_slice(arg: &str) {
println!("{}", arg);
}
@ -16,14 +14,14 @@ fn string(arg: String) {
}
fn main() {
???("blue");
???("red".to_string());
???(String::from("hi"));
???("rust is fun!".to_owned());
???("nice weather".into());
???(format!("Interpolation {}", "Station"));
???(&String::from("abc")[0..1]);
???(" hello there ".trim());
???("Happy Monday!".to_string().replace("Mon", "Tues"));
???("mY sHiFt KeY iS sTiCkY".to_lowercase());
string_slice("blue");
string("red".to_string());
string(String::from("hi"));
string("rust is fun!".to_owned());
string("nice weather".into());
string(format!("Interpolation {}", "Station"));
string_slice(&String::from("abc")[0..1]);
string_slice(" hello there ".trim());
string("Happy Monday!".to_string().replace("Mon", "Tues"));
string("mY sHiFt KeY iS sTiCkY".to_lowercase());
}

View File

@ -2,13 +2,13 @@
// Address all the TODOs to make the tests pass!
// Execute `rustlings hint structs1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
struct ColorClassicStruct {
// TODO: Something goes here
red: u8,
green: u8,
blue: u8,
}
struct ColorTupleStruct(/* TODO: Something goes here */);
struct ColorTupleStruct(u8, u8, u8);
#[derive(Debug)]
struct UnitLikeStruct;
@ -20,7 +20,11 @@ mod tests {
#[test]
fn classic_c_structs() {
// TODO: Instantiate a classic c struct!
// let green =
let green = ColorClassicStruct {
red: 0,
green: 255,
blue: 0,
};
assert_eq!(green.red, 0);
assert_eq!(green.green, 255);
@ -30,7 +34,7 @@ mod tests {
#[test]
fn tuple_structs() {
// TODO: Instantiate a tuple struct!
// let green =
let green = ColorTupleStruct(0, 255, 0);
assert_eq!(green.0, 0);
assert_eq!(green.1, 255);
@ -40,7 +44,7 @@ mod tests {
#[test]
fn unit_structs() {
// TODO: Instantiate a unit-like struct!
// let unit_like_struct =
let unit_like_struct = UnitLikeStruct;
let message = format!("{:?}s are fun!", unit_like_struct);
assert_eq!(message, "UnitLikeStructs are fun!");

View File

@ -2,8 +2,6 @@
// Address all the TODOs to make the tests pass!
// Execute `rustlings hint structs2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[derive(Debug)]
struct Order {
name: String,
@ -35,7 +33,11 @@ mod tests {
fn your_order() {
let order_template = create_order_template();
// TODO: Create your own order using the update syntax and template above!
// let your_order =
let your_order = Order {
name: "Hacker in Rust".to_string(),
count: 1,
..order_template
};
assert_eq!(your_order.name, "Hacker in Rust");
assert_eq!(your_order.year, order_template.year);
assert_eq!(your_order.made_by_phone, order_template.made_by_phone);

View File

@ -4,8 +4,6 @@
// Make the code compile and the tests pass!
// Execute `rustlings hint structs3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[derive(Debug)]
struct Package {
sender_country: String,
@ -26,12 +24,14 @@ impl Package {
}
}
fn is_international(&self) -> ??? {
fn is_international(&self) -> bool {
// Something goes here...
self.recipient_country != self.sender_country
}
fn get_fees(&self, cents_per_gram: i32) -> ??? {
fn get_fees(&self, cents_per_gram: i32) -> i32 {
// Something goes here...
self.weight_in_grams * cents_per_gram
}
}

View File

@ -7,12 +7,10 @@
// pass! Make the test fail!
// Execute `rustlings hint tests1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[cfg(test)]
mod tests {
#[test]
fn you_can_assert() {
assert!();
assert!(true);
}
}

View File

@ -3,12 +3,10 @@
// pass! Make the test fail!
// Execute `rustlings hint tests2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[cfg(test)]
mod tests {
#[test]
fn you_can_assert_eq() {
assert_eq!();
assert_eq!(2, 1 + 1);
}
}

View File

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

View File

@ -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};
@ -25,6 +23,7 @@ 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 {

View File

@ -3,9 +3,7 @@
// 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;
@ -14,14 +12,15 @@ struct JobStatus {
}
fn main() {
let status = Arc::new(JobStatus { jobs_completed: 0 });
// we need to mutate the status, so need Mutex lock
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;
status_shared.lock().unwrap().jobs_completed += 1;
});
handles.push(handle);
}
@ -29,6 +28,6 @@ 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 {}", ???);
println!("jobs completed {}", status.lock().unwrap().jobs_completed);
}
}

View File

@ -1,13 +1,12 @@
// 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;
use std::time::Duration;
#[derive(Debug)]
struct Queue {
length: u32,
first_half: Vec<u32>,
@ -28,6 +27,7 @@ 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 tx1 = tx.clone();
thread::spawn(move || {
for val in &qc1.first_half {
@ -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));
}
});

View File

@ -2,9 +2,7 @@
// Make me compile!
// Execute `rustlings hint variables1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
x = 5;
let x = 5;
println!("x has the value {}", x);
}

View File

@ -1,10 +1,8 @@
// variables2.rs
// Execute `rustlings hint variables2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let x;
let x = 0;
if x == 10 {
println!("x is ten!");
} else {

View File

@ -1,9 +1,7 @@
// variables3.rs
// Execute `rustlings hint variables3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let x: i32;
let x: i32 = 0;
println!("Number {}", x);
}

View File

@ -1,10 +1,8 @@
// variables4.rs
// Execute `rustlings hint variables4` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let x = 3;
let mut x = 3;
println!("Number {}", x);
x = 5; // don't change this line
println!("Number {}", x);

View File

@ -1,11 +1,9 @@
// variables5.rs
// Execute `rustlings hint variables5` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let number = "T-H-R-E-E"; // don't change this line
println!("Spell a Number : {}", number);
number = 3; // don't rename this variable
let number = 3; // don't rename this variable
println!("Number plus two is : {}", number + 2);
}

View File

@ -1,9 +1,7 @@
// variables6.rs
// Execute `rustlings hint variables6` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
const NUMBER = 3;
const NUMBER: i32 = 3;
fn main() {
println!("Number {}", NUMBER);
}

View File

@ -4,11 +4,10 @@
// Make me compile and pass the test!
// Execute `rustlings hint vecs1` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn array_and_vec() -> ([i32; 4], Vec<i32>) {
let a = [10, 20, 30, 40]; // a plain array
let v = // TODO: declare your vector here with the macro for vectors
// TODO: declare your vector here with the macro for vectors
let v = vec![10, 20, 30, 40];
(a, v)
}

View File

@ -6,13 +6,11 @@
//
// Execute `rustlings hint vecs2` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
for i in v.iter_mut() {
// TODO: Fill this up so that each element in the Vec `v` is
// multiplied by 2.
???
*i *= 2;
}
// At this point, `v` should be equal to [4, 8, 12, 16, 20].
@ -23,7 +21,7 @@ fn vec_map(v: &Vec<i32>) -> Vec<i32> {
v.iter().map(|num| {
// TODO: Do the same thing as above - but instead of mutating the
// Vec, you can just return the new number!
???
num * 2
}).collect()
}