This commit is contained in:
Yao Cui 2022-01-03 02:06:55 -05:00
parent d57c183028
commit 85e533e746
80 changed files with 360 additions and 131 deletions

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@ -24,12 +24,18 @@ impl From<CreationError> for ParsePosNonzeroError {
fn from(e: CreationError) -> Self { fn from(e: CreationError) -> Self {
// TODO: complete this implementation so that the `?` operator will // TODO: complete this implementation so that the `?` operator will
// work for `CreationError` // work for `CreationError`
Self::Creation(e)
} }
} }
// TODO: implement another instance of the `From` trait here so that the // TODO: implement another instance of the `From` trait here so that the
// `?` operator will work in the other place in the `FromStr` // `?` operator will work in the other place in the `FromStr`
// implementation below. // implementation below.
impl From<ParseIntError> for ParsePosNonzeroError {
fn from(e: ParseIntError) -> Self {
Self::ParseInt(e)
}
}
// Don't change anything below this line. // Don't change anything below this line.

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@ -47,9 +47,14 @@ impl From<ParseIntError> for ParseClimateError {
impl From<ParseFloatError> for ParseClimateError { impl From<ParseFloatError> for ParseClimateError {
fn from(e: ParseFloatError) -> Self { fn from(e: ParseFloatError) -> Self {
// TODO: Complete this function // TODO: Complete this function
Self::ParseFloat(e)
} }
} }
impl std::error::Error for ParseClimateError {
}
// TODO: Implement a missing trait so that `main()` below will compile. It // TODO: Implement a missing trait so that `main()` below will compile. It
// is not necessary to implement any methods inside the missing trait. // is not necessary to implement any methods inside the missing trait.
@ -63,7 +68,10 @@ impl Display for ParseClimateError {
use ParseClimateError::*; use ParseClimateError::*;
match self { match self {
NoCity => write!(f, "no city name"), NoCity => write!(f, "no city name"),
BadLen => write!(f, "incorrect number of fields"),
Empty => write!(f, "empty input"),
ParseFloat(e) => write!(f, "error parsing temperature: {}", e), ParseFloat(e) => write!(f, "error parsing temperature: {}", e),
ParseInt(e) => write!(f, "error parsing year: {}", e),
_ => write!(f, "unhandled error!"), _ => write!(f, "unhandled error!"),
} }
} }
@ -90,11 +98,19 @@ impl FromStr for Climate {
// cases. // cases.
fn from_str(s: &str) -> Result<Self, Self::Err> { fn from_str(s: &str) -> Result<Self, Self::Err> {
let v: Vec<_> = s.split(',').collect(); let v: Vec<_> = s.split(',').collect();
let (city, year, temp) = match &v[..] { let (city, yr, temp) = match &v[..] {
[city, year, temp] => (city.to_string(), year, temp), [city, year, temp] => (city.to_string(), year, temp),
[""] => return Err(ParseClimateError::Empty),
_ => return Err(ParseClimateError::BadLen), _ => return Err(ParseClimateError::BadLen),
}; };
let year: u32 = year.parse()?; if city.is_empty() {
return Err(ParseClimateError::NoCity);
}
let year: u32;
match yr.parse::<u32>() {
Ok(y) => year = y,
Err(e) => return Err(ParseClimateError::ParseInt(e))
}
let temp: f32 = temp.parse()?; let temp: f32 = temp.parse()?;
Ok(Climate { city, year, temp }) Ok(Climate { city, year, temp })
} }

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@ -6,7 +6,7 @@
fn main() { fn main() {
let mut res = 42; let mut res = 42;
let option = Some(12); let option = Some(12);
for x in option { if let Some(x) = option {
res += x; res += x;
} }
println!("{}", res); println!("{}", res);

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@ -16,12 +16,14 @@
use std::collections::HashMap; use std::collections::HashMap;
fn fruit_basket() -> HashMap<String, u32> { fn fruit_basket() -> HashMap<String, u32> {
let mut basket = // TODO: declare your hash map here. let mut basket = HashMap::new();
// Two bananas are already given for you :) // Two bananas are already given for you :)
basket.insert(String::from("banana"), 2); basket.insert(String::from("banana"), 2);
// TODO: Put more fruits in your basket here. // TODO: Put more fruits in your basket here.
basket.insert(String::from("apple"), 2);
basket.insert(String::from("peach"), 3);
basket basket
} }

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@ -38,6 +38,7 @@ fn fruit_basket(basket: &mut HashMap<Fruit, u32>) {
// TODO: Put new fruits if not already present. Note that you // TODO: Put new fruits if not already present. Note that you
// are not allowed to put any type of fruit that's already // are not allowed to put any type of fruit that's already
// present! // present!
basket.entry(fruit).or_insert(1);
} }
} }

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@ -8,7 +8,7 @@
fn array_and_vec() -> ([i32; 4], Vec<i32>) { fn array_and_vec() -> ([i32; 4], Vec<i32>) {
let a = [10, 20, 30, 40]; // a plain array let a = [10, 20, 30, 40]; // a plain array
let v = // TODO: declare your vector here with the macro for vectors let v = vec![10, 20, 30, 40];// TODO: declare your vector here with the macro for vectors
(a, v) (a, v)
} }

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@ -13,6 +13,7 @@ fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
for i in v.iter_mut() { for i in v.iter_mut() {
// TODO: Fill this up so that each element in the Vec `v` is // TODO: Fill this up so that each element in the Vec `v` is
// multiplied by 2. // multiplied by 2.
*i *= 2
} }
// At this point, `v` should be equal to [4, 8, 12, 16, 20]. // At this point, `v` should be equal to [4, 8, 12, 16, 20].

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@ -6,13 +6,15 @@
// Obtain the number of bytes (not characters) in the given argument // Obtain the number of bytes (not characters) in the given argument
// Add the AsRef trait appropriately as a trait bound // Add the AsRef trait appropriately as a trait bound
fn byte_counter<T>(arg: T) -> usize { fn byte_counter<T>(arg: T) -> usize
where T: AsRef<str> {
arg.as_ref().as_bytes().len() arg.as_ref().as_bytes().len()
} }
// Obtain the number of characters (not bytes) in the given argument // Obtain the number of characters (not bytes) in the given argument
// Add the AsRef trait appropriately as a trait bound // Add the AsRef trait appropriately as a trait bound
fn char_counter<T>(arg: T) -> usize { fn char_counter<T>(arg: T) -> usize
where T: AsRef<str> {
arg.as_ref().chars().count() arg.as_ref().chars().count()
} }

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@ -37,6 +37,24 @@ impl Default for Person {
impl From<&str> for Person { impl From<&str> for Person {
fn from(s: &str) -> Person { fn from(s: &str) -> Person {
let v: Vec<_> = s.split(",").collect();
// println!("{:?}", v);
let (name, age) = match &v[..] {
["", _] => return Default::default(),
[_, ""] => return Default::default(),
[name, age] => (name.to_string(), age),
_ => return Default::default()
};
let age: usize = match age.parse() {
Ok(age) => age,
_ => return Default::default()
};
Self {
name,
age
}
} }
} }

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@ -41,6 +41,22 @@ enum ParsePersonError {
impl FromStr for Person { impl FromStr for Person {
type Err = ParsePersonError; type Err = ParsePersonError;
fn from_str(s: &str) -> Result<Person, Self::Err> { fn from_str(s: &str) -> Result<Person, Self::Err> {
let v: Vec<_> = s.split(",").collect();
let (name, age) = match &v[..] {
[""] => return Err(ParsePersonError::Empty),
["", _] => return Err(ParsePersonError::NoName),
[name, age] => (name.to_string(), age),
_ => return Err(ParsePersonError::BadLen)
};
let age: usize = match age.parse() {
Ok(age) => age,
Err(e) => return Err(ParsePersonError::ParseInt(e))
};
Ok(Self {
name, age
})
} }
} }

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@ -36,6 +36,24 @@ enum IntoColorError {
impl TryFrom<(i16, i16, i16)> for Color { impl TryFrom<(i16, i16, i16)> for Color {
type Error = IntoColorError; type Error = IntoColorError;
fn try_from(tuple: (i16, i16, i16)) -> Result<Self, Self::Error> { fn try_from(tuple: (i16, i16, i16)) -> Result<Self, Self::Error> {
let red = match u8::try_from(tuple.0) {
Ok(red) => red,
_ => return Err(Self::Error::IntConversion),
};
let green = match u8::try_from(tuple.1) {
Ok(green) => green,
_ => return Err(Self::Error::IntConversion),
};
let blue = match u8::try_from(tuple.2) {
Ok(blue) => blue,
_ => return Err(Self::Error::IntConversion),
};
Ok(Self {
red, green, blue
})
} }
} }
@ -43,6 +61,7 @@ impl TryFrom<(i16, i16, i16)> for Color {
impl TryFrom<[i16; 3]> for Color { impl TryFrom<[i16; 3]> for Color {
type Error = IntoColorError; type Error = IntoColorError;
fn try_from(arr: [i16; 3]) -> Result<Self, Self::Error> { fn try_from(arr: [i16; 3]) -> Result<Self, Self::Error> {
Self::try_from((arr[0], arr[1], arr[2]))
} }
} }
@ -50,6 +69,11 @@ impl TryFrom<[i16; 3]> for Color {
impl TryFrom<&[i16]> for Color { impl TryFrom<&[i16]> for Color {
type Error = IntoColorError; type Error = IntoColorError;
fn try_from(slice: &[i16]) -> Result<Self, Self::Error> { fn try_from(slice: &[i16]) -> Result<Self, Self::Error> {
if slice.len() != 3 {
return Err(Self::Error::BadLen);
}
Self::try_from((slice[0], slice[1], slice[2]))
} }
} }

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@ -9,7 +9,7 @@
fn average(values: &[f64]) -> f64 { fn average(values: &[f64]) -> f64 {
let total = values.iter().fold(0.0, |a, b| a + b); let total = values.iter().fold(0.0, |a, b| a + b);
total / values.len() total / (values.len() as f64)
} }
fn main() { fn main() {

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@ -6,6 +6,10 @@
#[derive(Debug)] #[derive(Debug)]
enum Message { enum Message {
// TODO: define a few types of messages as used below // TODO: define a few types of messages as used below
Quit,
Echo,
Move,
ChangeColor,
} }
fn main() { fn main() {

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@ -6,6 +6,10 @@
#[derive(Debug)] #[derive(Debug)]
enum Message { enum Message {
// TODO: define the different variants used below // TODO: define the different variants used below
Move {x: i32, y: i32},
Echo (String),
ChangeColor (i32, i32, i32),
Quit,
} }
impl Message { impl Message {

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@ -2,11 +2,15 @@
// Address all the TODOs to make the tests pass! // Address all the TODOs to make the tests pass!
// I AM NOT DONE // I AM NOT DONE
#[derive(Debug)]
enum Message { enum Message {
// TODO: implement the message variant types based on their usage below // TODO: implement the message variant types based on their usage below
ChangeColor((u8, u8, u8)),
Echo(String),
Move(Point),
Quit,
} }
#[derive(Debug)]
struct Point { struct Point {
x: u8, x: u8,
y: u8, y: u8,
@ -37,6 +41,20 @@ impl State {
fn process(&mut self, message: Message) { fn process(&mut self, message: Message) {
// TODO: create a match expression to process the different message variants // TODO: create a match expression to process the different message variants
match message {
Message::ChangeColor((x, y, z)) => {
self.color = (x, y, z);
},
Message::Move(p) => {
self.position = p;
},
Message::Quit => {
self.quit = true;
},
Message::Echo(s) => {
println!("{}", s);
}
}
} }
} }

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@ -8,12 +8,12 @@
// I AM NOT DONE // 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.len() > 0 { if name.len() > 0 {
Some(format!("Hi! My name is {}", name)) Ok(format!("Hi! My name is {}", name))
} else { } else {
// Empty names aren't allowed. // Empty names aren't allowed.
None Err("`name` was empty; it must be nonempty.".to_string())
} }
} }
@ -28,7 +28,7 @@ mod tests {
fn generates_nametag_text_for_a_nonempty_name() { fn generates_nametag_text_for_a_nonempty_name() {
assert_eq!( assert_eq!(
generate_nametag_text("Beyoncé".into()), generate_nametag_text("Beyoncé".into()),
Some("Hi! My name is Beyoncé".into()) Ok("Hi! My name is Beyoncé".into())
); );
} }

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@ -23,9 +23,12 @@ use std::num::ParseIntError;
pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> { pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
let processing_fee = 1; let processing_fee = 1;
let cost_per_item = 5; let cost_per_item = 5;
let qty = item_quantity.parse::<i32>(); match item_quantity.parse::<i32>() {
Ok(qty) => {
Ok(qty * cost_per_item + processing_fee) Ok(qty * cost_per_item + processing_fee)
},
e => e
}
} }
#[cfg(test)] #[cfg(test)]

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@ -12,7 +12,7 @@ fn main() {
let mut tokens = 100; let mut tokens = 100;
let pretend_user_input = "8"; let pretend_user_input = "8";
let cost = total_cost(pretend_user_input)?; let cost = total_cost(pretend_user_input).unwrap();
if cost > tokens { if cost > tokens {
println!("You can't afford that many!"); println!("You can't afford that many!");
@ -25,7 +25,8 @@ fn main() {
pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> { pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
let processing_fee = 1; let processing_fee = 1;
let cost_per_item = 5; let cost_per_item = 5;
let qty = item_quantity.parse::<i32>()?; match item_quantity.parse::<i32>() {
Ok(qty) => Ok(qty * cost_per_item + processing_fee),
Ok(qty * cost_per_item + processing_fee) e => e
}
} }

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@ -14,7 +14,13 @@ enum CreationError {
impl PositiveNonzeroInteger { impl PositiveNonzeroInteger {
fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> { fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> {
Ok(PositiveNonzeroInteger(value as u64)) if value < 0 {
Err(CreationError::Negative)
} else if value == 0 {
Err(CreationError::Zero)
} else {
Ok(PositiveNonzeroInteger(value as u64))
}
} }
} }

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@ -11,7 +11,7 @@ use std::fmt;
use std::num::ParseIntError; use std::num::ParseIntError;
// TODO: update the return type of `main()` to make this compile. // TODO: update the return type of `main()` to make this compile.
fn main() -> Result<(), ParseIntError> { fn main() -> Result<(), Box<dyn error::Error>> {
let pretend_user_input = "42"; let pretend_user_input = "42";
let x: i64 = pretend_user_input.parse()?; let x: i64 = pretend_user_input.parse()?;
println!("output={:?}", PositiveNonzeroInteger::new(x)?); println!("output={:?}", PositiveNonzeroInteger::new(x)?);

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@ -24,6 +24,9 @@ impl ParsePosNonzeroError {
ParsePosNonzeroError::Creation(err) ParsePosNonzeroError::Creation(err)
} }
// TODO: add another error conversion function here. // TODO: add another error conversion function here.
fn from_parseint(err: ParseIntError) -> ParsePosNonzeroError {
ParsePosNonzeroError::ParseInt(err)
}
} }
fn parse_pos_nonzero(s: &str) fn parse_pos_nonzero(s: &str)
@ -31,9 +34,15 @@ fn parse_pos_nonzero(s: &str)
{ {
// TODO: change this to return an appropriate error instead of panicking // TODO: change this to return an appropriate error instead of panicking
// when `parse()` returns an error. // when `parse()` returns an error.
let x: i64 = s.parse().unwrap(); match s.parse() {
PositiveNonzeroInteger::new(x) Ok(x) => {
.map_err(ParsePosNonzeroError::from_creation) match PositiveNonzeroInteger::new(x) {
Ok(pni) => Ok(pni),
Err(e) => Err(ParsePosNonzeroError::from_creation(e))
}
},
Err(e) => Err(ParsePosNonzeroError::from_parseint(e))
}
} }
// Don't change anything below this line. // Don't change anything below this line.

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@ -3,6 +3,10 @@
// I AM NOT DONE // I AM NOT DONE
fn call_me() {
}
fn main() { fn main() {
call_me(); call_me();
} }

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@ -7,7 +7,7 @@ fn main() {
call_me(3); call_me(3);
} }
fn call_me(num:) { fn call_me(num: i32) {
for i in 0..num { for i in 0..num {
println!("Ring! Call number {}", i + 1); println!("Ring! Call number {}", i + 1);
} }

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@ -4,7 +4,7 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
call_me(); call_me(3);
} }
fn call_me(num: u32) { fn call_me(num: u32) {

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@ -11,7 +11,7 @@ fn main() {
println!("Your sale price is {}", sale_price(original_price)); println!("Your sale price is {}", sale_price(original_price));
} }
fn sale_price(price: i32) -> { fn sale_price(price: i32) -> i32 {
if is_even(price) { if is_even(price) {
price - 10 price - 10
} else { } else {

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@ -9,5 +9,5 @@ fn main() {
} }
fn square(num: i32) -> i32 { fn square(num: i32) -> i32 {
num * num; num * num
} }

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@ -6,6 +6,6 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
let mut shopping_list: Vec<?> = Vec::new(); let mut shopping_list: Vec<&str> = Vec::new();
shopping_list.push("milk"); shopping_list.push("milk");
} }

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@ -5,12 +5,12 @@
// I AM NOT DONE // I AM NOT DONE
struct Wrapper { struct Wrapper<T> {
value: u32, value: T,
} }
impl Wrapper { impl<T> Wrapper<T> {
pub fn new(value: u32) -> Self { pub fn new(value: T) -> Self {
Wrapper { value } Wrapper { value }
} }
} }

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@ -12,13 +12,13 @@
// I AM NOT DONE // I AM NOT DONE
pub struct ReportCard { pub struct ReportCard<T> {
pub grade: f32, pub grade: T,
pub student_name: String, pub student_name: String,
pub student_age: u8, pub student_age: u8,
} }
impl ReportCard { impl<T: std::fmt::Display> ReportCard<T> {
pub fn print(&self) -> String { pub fn print(&self) -> String {
format!("{} ({}) - achieved a grade of {}", format!("{} ({}) - achieved a grade of {}",
&self.student_name, &self.student_age, &self.grade) &self.student_name, &self.student_age, &self.grade)
@ -46,7 +46,7 @@ mod tests {
fn generate_alphabetic_report_card() { fn generate_alphabetic_report_card() {
// TODO: Make sure to change the grade here after you finish the exercise. // TODO: Make sure to change the grade here after you finish the exercise.
let report_card = ReportCard { let report_card = ReportCard {
grade: 2.1, grade: "A+",
student_name: "Gary Plotter".to_string(), student_name: "Gary Plotter".to_string(),
student_age: 11, student_age: 11,
}; };

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@ -8,6 +8,11 @@ pub fn bigger(a: i32, b: i32) -> i32 {
// - another function call // - another function call
// - additional variables // - additional variables
// Execute `rustlings hint if1` for hints // Execute `rustlings hint if1` for hints
if a > b {
a
} else {
b
}
} }
// Don't mind this for now :) // Don't mind this for now :)

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@ -9,8 +9,10 @@
pub fn fizz_if_foo(fizzish: &str) -> &str { pub fn fizz_if_foo(fizzish: &str) -> &str {
if fizzish == "fizz" { if fizzish == "fizz" {
"foo" "foo"
} else if fizzish == "fuzz" {
"bar"
} else { } else {
1 "baz"
} }
} }

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@ -3,6 +3,7 @@
// I AM NOT DONE // I AM NOT DONE
#[macro_export]
macro_rules! my_macro { macro_rules! my_macro {
() => { () => {
println!("Check out my macro!"); println!("Check out my macro!");
@ -10,5 +11,5 @@ macro_rules! my_macro {
} }
fn main() { fn main() {
my_macro(); my_macro!();
} }

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@ -7,6 +7,7 @@ fn main() {
my_macro!(); my_macro!();
} }
#[macro_export]
macro_rules! my_macro { macro_rules! my_macro {
() => { () => {
println!("Check out my macro!"); println!("Check out my macro!");

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@ -4,6 +4,7 @@
// I AM NOT DONE // I AM NOT DONE
#[macro_use]
mod macros { mod macros {
macro_rules! my_macro { macro_rules! my_macro {
() => { () => {

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@ -6,10 +6,10 @@
macro_rules! my_macro { macro_rules! my_macro {
() => { () => {
println!("Check out my macro!"); println!("Check out my macro!");
} };
($val:expr) => { ($val:expr) => {
println!("Look at this other macro: {}", $val); println!("Look at this other macro: {}", $val);
} };
} }
fn main() { fn main() {

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@ -9,7 +9,7 @@ mod sausage_factory {
String::from("Ginger") String::from("Ginger")
} }
fn make_sausage() { pub fn make_sausage() {
get_secret_recipe(); get_secret_recipe();
println!("sausage!"); println!("sausage!");
} }

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@ -8,8 +8,8 @@
mod delicious_snacks { mod delicious_snacks {
// TODO: Fix these use statements // TODO: Fix these use statements
use self::fruits::PEAR as ??? pub use self::fruits::PEAR as fruit;
use self::veggies::CUCUMBER as ??? pub use self::veggies::CUCUMBER as veggie;
mod fruits { mod fruits {
pub const PEAR: &'static str = "Pear"; pub const PEAR: &'static str = "Pear";

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@ -8,7 +8,7 @@
// I AM NOT DONE // I AM NOT DONE
// TODO: Complete this use statement // TODO: Complete this use statement
use ??? use std::time::{ SystemTime, UNIX_EPOCH };
fn main() { fn main() {
match SystemTime::now().duration_since(UNIX_EPOCH) { match SystemTime::now().duration_since(UNIX_EPOCH) {

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@ -4,9 +4,9 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
let vec0 = Vec::new(); let mut vec0 = Vec::new();
let vec1 = fill_vec(vec0); let mut vec1 = fill_vec(vec0);
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1); println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
@ -15,8 +15,7 @@ fn main() {
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1); 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> {
let mut vec = vec;
vec.push(22); vec.push(22);
vec.push(44); vec.push(44);

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@ -7,7 +7,7 @@
fn main() { fn main() {
let vec0 = Vec::new(); let vec0 = Vec::new();
let mut vec1 = fill_vec(vec0); let mut vec1 = fill_vec(&vec0);
// Do not change the following line! // Do not change the following line!
println!("{} has length {} content `{:?}`", "vec0", vec0.len(), vec0); println!("{} has length {} content `{:?}`", "vec0", vec0.len(), vec0);
@ -17,8 +17,8 @@ fn main() {
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1); println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
} }
fn fill_vec(vec: Vec<i32>) -> Vec<i32> { fn fill_vec(vec: &Vec<i32>) -> Vec<i32> {
let mut vec = vec; let mut vec = vec.clone();
vec.push(22); vec.push(22);
vec.push(44); vec.push(44);

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@ -6,7 +6,7 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
let vec0 = Vec::new(); let mut vec0 = Vec::new();
let mut vec1 = fill_vec(vec0); let mut vec1 = fill_vec(vec0);
@ -17,7 +17,7 @@ fn main() {
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1); 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(22);
vec.push(44); vec.push(44);
vec.push(66); vec.push(66);

View File

@ -7,9 +7,8 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { 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); println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
@ -20,7 +19,7 @@ fn main() {
// `fill_vec()` no longer takes `vec: Vec<i32>` as argument // `fill_vec()` no longer takes `vec: Vec<i32>` as argument
fn fill_vec() -> Vec<i32> { fn fill_vec() -> Vec<i32> {
let mut vec = vec; let mut vec = Vec::new();
vec.push(22); vec.push(22);
vec.push(44); vec.push(44);

View File

@ -8,8 +8,8 @@
fn main() { fn main() {
let mut x = 100; let mut x = 100;
let y = &mut x; let y = &mut x;
let z = &mut x;
*y += 100; *y += 100;
let z = &mut x;
*z += 1000; *z += 1000;
assert_eq!(x, 1200); assert_eq!(x, 1200);
} }

View File

@ -9,15 +9,15 @@ fn print_number(maybe_number: Option<u16>) {
} }
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] = [None; 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

@ -6,7 +6,7 @@
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 Some(word) = optional_word {
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");
@ -19,7 +19,7 @@ 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(Some(integer)) = optional_integers_vec.pop() {
println!("current value: {}", integer); println!("current value: {}", integer);
} }
} }

View File

@ -11,9 +11,14 @@ struct Point {
fn main() { 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.as_ref() {
Some(p) => println!("Co-ordinates are {},{} ", p.x, p.y), Some(p) => println!("Co-ordinates are {},{} ", p.x, p.y),
_ => println!("no match"), _ => println!("no match"),
} }
match y {
Some(ref p) => println!("Co-ordinates are {},{} ", p.x, p.y),
_ => println!("no match"),
}
y; // Fix without deleting this line. y; // Fix without deleting this line.
} }

View File

@ -12,7 +12,7 @@ fn main() {
println!("Good morning!"); println!("Good morning!");
} }
let // Finish the rest of this line like the example! Or make it be false! let is_evening = true; // Finish the rest of this line like the example! Or make it be false!
if is_evening { if is_evening {
println!("Good evening!"); println!("Good evening!");
} }

View File

@ -1,4 +1,3 @@
// primitive_types2.rs
// Fill in the rest of the line that has code missing! // Fill in the rest of the line that has code missing!
// No hints, there's no tricks, just get used to typing these :) // No hints, there's no tricks, just get used to typing these :)
@ -16,7 +15,7 @@ fn main() {
println!("Neither alphabetic nor numeric!"); println!("Neither alphabetic nor numeric!");
} }
let // Finish this line like the example! What's your favorite character? let your_character = '😊'; // Finish this line like the example! What's your favorite character?
// Try a letter, try a number, try a special character, try a character // Try a letter, try a number, try a special character, try a character
// from a different language than your own, try an emoji! // from a different language than your own, try an emoji!
if your_character.is_alphabetic() { if your_character.is_alphabetic() {

View File

@ -5,7 +5,7 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
let a = ??? let a = [1; 100];
if a.len() >= 100 { if a.len() >= 100 {
println!("Wow, that's a big array!"); println!("Wow, that's a big array!");

View File

@ -8,7 +8,7 @@
fn slice_out_of_array() { fn slice_out_of_array() {
let a = [1, 2, 3, 4, 5]; let a = [1, 2, 3, 4, 5];
let nice_slice = ??? let nice_slice = &a[1..4];
assert_eq!([2, 3, 4], nice_slice) assert_eq!([2, 3, 4], nice_slice)
} }

View File

@ -6,7 +6,7 @@
fn main() { fn main() {
let cat = ("Furry McFurson", 3.5); let cat = ("Furry McFurson", 3.5);
let /* your pattern here */ = cat; let (name, age) = cat;
println!("{} is {} years old.", name, age); println!("{} is {} years old.", name, age);
} }

View File

@ -9,7 +9,7 @@
fn indexing_tuple() { fn indexing_tuple() {
let numbers = (1, 2, 3); let numbers = (1, 2, 3);
// Replace below ??? with the tuple indexing syntax. // Replace below ??? with the tuple indexing syntax.
let second = ???; let second = numbers.1;
assert_eq!(2, second, assert_eq!(2, second,
"This is not the 2nd number in the tuple!") "This is not the 2nd number in the tuple!")

View File

@ -12,6 +12,14 @@
// Put your function here! // Put your function here!
// fn calculate_apple_price { // fn calculate_apple_price {
fn calculate_apple_price(quantity: usize) -> usize {
if quantity <= 40 {
quantity * 2
} else {
quantity * 1
}
}
// Don't modify this function! // Don't modify this function!
#[test] #[test]
fn verify_test() { fn verify_test() {

View File

@ -17,14 +17,14 @@ fn string(arg: String) {
} }
fn main() { fn main() {
???("blue"); string_slice("blue");
???("red".to_string()); string("red".to_string());
???(String::from("hi")); string(String::from("hi"));
???("rust is fun!".to_owned()); string("rust is fun!".to_owned());
???("nice weather".into()); string("nice weather".into());
???(format!("Interpolation {}", "Station")); string(format!("Interpolation {}", "Station"));
???(&String::from("abc")[0..1]); string_slice(&String::from("abc")[0..1]);
???(" hello there ".trim()); string_slice(" hello there ".trim());
???("Happy Monday!".to_string().replace("Mon", "Tues")); string("Happy Monday!".to_string().replace("Mon", "Tues"));
???("mY sHiFt KeY iS sTiCkY".to_lowercase()); string("mY sHiFt KeY iS sTiCkY".to_lowercase());
} }

View File

@ -19,12 +19,12 @@ 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

@ -6,6 +6,11 @@
// Write a macro that passes the quiz! No hints this time, you can do it! // Write a macro that passes the quiz! No hints this time, you can do it!
// I AM NOT DONE // I AM NOT DONE
macro_rules! my_macro {
($val:expr) => {
format!("Hello {}", $val)
};
}
#[cfg(test)] #[cfg(test)]
mod tests { mod tests {

View File

@ -23,17 +23,19 @@
#![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;
use std::sync::Mutex;
fn main() { fn main() {
let numbers: Vec<_> = (0..100u32).collect(); let numbers: Vec<_> = (0..100u32).collect();
let shared_numbers = // TODO let shared_numbers = Arc::new(Mutex::new(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 mut i = offset; let mut i = offset;
let mut sum = 0; let mut sum = 0;
let child_numbers = child_numbers.lock().unwrap();
while i < child_numbers.len() { while i < child_numbers.len() {
sum += child_numbers[i]; sum += child_numbers[i];
i += 8; i += 8;

View File

@ -20,7 +20,7 @@
#[derive(PartialEq, Debug)] #[derive(PartialEq, Debug)]
pub enum List { pub enum List {
Cons(i32, List), Cons(i32, Box<List>),
Nil, Nil,
} }
@ -33,11 +33,11 @@ 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!() List::Cons(0, Box::new(List::Nil))
} }
#[cfg(test)] #[cfg(test)]

View File

@ -13,12 +13,12 @@
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 2.1 assert_eq!(my_iterable_fav_fruits.next(), Some(&"peach")); // TODO: Step 2.1
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 3 assert_eq!(my_iterable_fav_fruits.next(), None); // TODO: Step 3
} }

View File

@ -12,7 +12,11 @@ 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 s = first.to_string().to_uppercase();
s.push_str(&input[1..]);
s
},
} }
} }
@ -21,7 +25,11 @@ 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 v = Vec::new();
for word in words {
v.push(capitalize_first(word));
}
v
} }
// Step 3. // Step 3.
@ -29,7 +37,8 @@ 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() let v = capitalize_words_vector(words);
v.join("")
} }
#[cfg(test)] #[cfg(test)]

View File

@ -22,20 +22,34 @@ 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 {
Err(DivisionError::DivideByZero)
} else {
if a % b == 0 {
Ok(a / b)
} else {
Err(DivisionError::NotDivisible(
NotDivisibleError{dividend: a, divisor: 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 = numbers.into_iter().map(|n| divide(n, 27).unwrap()).collect();
Ok(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 = numbers.into_iter().map(|n| divide(n, 27)).collect();
division_results
} }
#[cfg(test)] #[cfg(test)]

View File

@ -12,6 +12,11 @@ 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.
let mut res = 1;
for i in 1..num+1 {
res *= i;
}
res
} }
#[cfg(test)] #[cfg(test)]

View File

@ -34,6 +34,13 @@ fn count_for(map: &HashMap<String, Progress>, value: Progress) -> usize {
fn count_iterator(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 is a hashmap with String keys and Progress values.
// map = { "variables1": Complete, "from_str": None, ... } // map = { "variables1": Complete, "from_str": None, ... }
let mut count = 0;
for (_, val) in map.iter() {
if val == &value {
count += 1;
}
}
count
} }
fn count_collection_for(collection: &[HashMap<String, Progress>], value: Progress) -> usize { fn count_collection_for(collection: &[HashMap<String, Progress>], value: Progress) -> usize {
@ -52,6 +59,15 @@ fn count_collection_iterator(collection: &[HashMap<String, Progress>], value: Pr
// collection is a slice of hashmaps. // collection is a slice of hashmaps.
// collection = [{ "variables1": Complete, "from_str": None, ... }, // collection = [{ "variables1": Complete, "from_str": None, ... },
// { "variables2": Complete, ... }, ... ] // { "variables2": Complete, ... }, ... ]
let mut count = 0;
for map in collection.iter() {
for (_, val) in map.iter() {
if val == &value {
count += 1;
}
}
}
count
} }
#[cfg(test)] #[cfg(test)]

View File

@ -10,5 +10,5 @@ fn main() {
} }
fn current_favorite_color() -> String { fn current_favorite_color() -> String {
"blue" "blue".to_string()
} }

View File

@ -6,7 +6,7 @@
fn main() { fn main() {
let word = String::from("green"); // Try not changing this line :) 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!"); println!("That is a color word I know!");
} else { } else {
println!("That is not a color word I know."); println!("That is not a color word I know.");

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@ -3,11 +3,12 @@
// I AM NOT DONE // I AM NOT DONE
struct ColorClassicStruct { struct ColorClassicStruct<'a> {
// TODO: Something goes here name: &'a str,
hex: &'a str
} }
struct ColorTupleStruct(/* TODO: Something goes here */); struct ColorTupleStruct<'a>(&'a str, &'a str);
#[derive(Debug)] #[derive(Debug)]
struct UnitStruct; struct UnitStruct;
@ -19,7 +20,7 @@ mod tests {
#[test] #[test]
fn classic_c_structs() { fn classic_c_structs() {
// TODO: Instantiate a classic c struct! // TODO: Instantiate a classic c struct!
// let green = let green = ColorClassicStruct { name: "green", hex: "#00FF00" };
assert_eq!(green.name, "green"); assert_eq!(green.name, "green");
assert_eq!(green.hex, "#00FF00"); assert_eq!(green.hex, "#00FF00");
@ -28,7 +29,7 @@ mod tests {
#[test] #[test]
fn tuple_structs() { fn tuple_structs() {
// TODO: Instantiate a tuple struct! // TODO: Instantiate a tuple struct!
// let green = let green = ColorTupleStruct ( "green", "#00FF00" );
assert_eq!(green.0, "green"); assert_eq!(green.0, "green");
assert_eq!(green.1, "#00FF00"); assert_eq!(green.1, "#00FF00");
@ -36,8 +37,8 @@ mod tests {
#[test] #[test]
fn unit_structs() { fn unit_structs() {
// TODO: Instantiate a unit struct! // TODO: Instantiate a unit struct
// let unit_struct = let unit_struct = UnitStruct;
let message = format!("{:?}s are fun!", unit_struct); let message = format!("{:?}s are fun!", unit_struct);
assert_eq!(message, "UnitStructs are fun!"); assert_eq!(message, "UnitStructs are fun!");

View File

@ -34,7 +34,15 @@ mod tests {
fn your_order() { fn your_order() {
let order_template = create_order_template(); let order_template = create_order_template();
// TODO: Create your own order using the update syntax and template above! // TODO: Create your own order using the update syntax and template above!
// let your_order = let your_order = Order {
name: String::from("Hacker in Rust"),
year: 2019,
made_by_phone: false,
made_by_mobile: false,
made_by_email: true,
item_number: 123,
count: 1,
};
assert_eq!(your_order.name, "Hacker in Rust"); assert_eq!(your_order.name, "Hacker in Rust");
assert_eq!(your_order.year, order_template.year); assert_eq!(your_order.year, order_template.year);
assert_eq!(your_order.made_by_phone, order_template.made_by_phone); assert_eq!(your_order.made_by_phone, order_template.made_by_phone);

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@ -17,6 +17,7 @@ impl Package {
fn new(sender_country: String, recipient_country: String, weight_in_grams: i32) -> Package { fn new(sender_country: String, recipient_country: String, weight_in_grams: i32) -> Package {
if weight_in_grams <= 0 { if weight_in_grams <= 0 {
// Something goes here... // Something goes here...
panic!("Weight of package is less than 0.");
} else { } else {
return Package { return Package {
sender_country, sender_country,
@ -26,12 +27,12 @@ impl Package {
} }
} }
fn is_international(&self) -> ??? { fn is_international(&self) -> bool {
// Something goes here... self.sender_country != self.recipient_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
} }
} }
@ -73,7 +74,7 @@ mod tests {
let sender_country = String::from("Spain"); let sender_country = String::from("Spain");
let recipient_country = String::from("Spain"); let recipient_country = String::from("Spain");
let cents_per_gram = ???; let cents_per_gram = 3;
let package = Package::new(sender_country, recipient_country, 1500); let package = Package::new(sender_country, recipient_country, 1500);

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@ -12,6 +12,6 @@
mod tests { mod tests {
#[test] #[test]
fn you_can_assert() { fn you_can_assert() {
assert!(); assert!(true);
} }
} }

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@ -8,6 +8,6 @@
mod tests { mod tests {
#[test] #[test]
fn you_can_assert_eq() { fn you_can_assert_eq() {
assert_eq!(); assert_eq!(1, 1);
} }
} }

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@ -16,11 +16,11 @@ 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(1));
} }
} }

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@ -9,6 +9,7 @@
// I AM NOT DONE // I AM NOT DONE
use std::sync::Arc; use std::sync::Arc;
use std::sync::Mutex;
use std::thread; use std::thread;
use std::time::Duration; use std::time::Duration;
@ -17,15 +18,15 @@ struct JobStatus {
} }
fn main() { fn main() {
let status = Arc::new(JobStatus { jobs_completed: 0 }); let status = Arc::new(Mutex::new( JobStatus { jobs_completed: 0 }));
let status_shared = status.clone(); let status_shared = status.clone();
thread::spawn(move || { thread::spawn(move || {
for _ in 0..10 { for _ in 0..10 {
thread::sleep(Duration::from_millis(250)); thread::sleep(Duration::from_millis(250));
status_shared.jobs_completed += 1; status_shared.lock().unwrap().jobs_completed += 1;
} }
}); });
while status.jobs_completed < 10 { while status.lock().unwrap().jobs_completed < 10 {
println!("waiting... "); println!("waiting... ");
thread::sleep(Duration::from_millis(500)); thread::sleep(Duration::from_millis(500));
} }

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@ -16,6 +16,11 @@ trait AppendBar {
impl AppendBar for String { impl AppendBar for String {
//Add your code here //Add your code here
fn append_bar(self) -> Self {
let mut s = self.clone();
s.push_str("Bar");
s
}
} }
fn main() { fn main() {

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@ -17,6 +17,13 @@ trait AppendBar {
} }
//TODO: Add your code here //TODO: Add your code here
impl AppendBar for Vec<String> {
fn append_bar(self) -> Self {
let mut v = self.clone();
v.push("Bar".to_string());
return v;
}
}
#[cfg(test)] #[cfg(test)]
mod tests { mod tests {

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@ -9,6 +9,6 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
x = 5; let x = 5;
println!("x has the value {}", x); println!("x has the value {}", x);
} }

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@ -4,7 +4,7 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
let x; let x = 10;
if x == 10 { if x == 10 {
println!("Ten!"); println!("Ten!");
} else { } else {

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@ -4,7 +4,7 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
let x = 3; let mut x = 3;
println!("Number {}", x); println!("Number {}", x);
x = 5; // don't change this line x = 5; // don't change this line
println!("Number {}", x); println!("Number {}", x);

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@ -4,6 +4,6 @@
// I AM NOT DONE // I AM NOT DONE
fn main() { fn main() {
let x: i32; let x: i32 = 10;
println!("Number {}", x); println!("Number {}", x);
} }

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@ -6,6 +6,6 @@
fn main() { fn main() {
let number = "T-H-R-E-E"; // don't change this line let number = "T-H-R-E-E"; // don't change this line
println!("Spell a Number : {}", number); println!("Spell a Number : {}", number);
number = 3; let number = 3;
println!("Number plus two is : {}", number + 2); println!("Number plus two is : {}", number + 2);
} }

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@ -3,7 +3,7 @@
// I AM NOT DONE // I AM NOT DONE
const NUMBER = 3; const NUMBER: i8 = 3;
fn main() { fn main() {
println!("Number {}", NUMBER); println!("Number {}", NUMBER);
} }