move, vecs, and primitives

This commit is contained in:
Alex Sudbinin 2022-09-30 21:31:50 -07:00
parent 303094ebee
commit d5d8cb2bf0
14 changed files with 33 additions and 64 deletions

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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.to_owned();
vec.push(22);
vec.push(44);

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@ -3,12 +3,10 @@
// (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();
let mut vec0 = Vec::new();
let mut vec1 = fill_vec(vec0);
let vec1 = fill_vec(&mut vec0);
println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
@ -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(vec: &mut Vec<i32>) -> &mut 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::new();
vec.push(22);
vec.push(44);

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@ -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);
}

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@ -2,24 +2,22 @@
// 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);
}

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@ -2,8 +2,6 @@
// Fill in the rest of the line that has code missing!
// No hints, there's no tricks, just get used to typing these :)
// I AM NOT DONE
fn main() {
// Booleans (`bool`)
@ -12,7 +10,7 @@ fn main() {
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 {
println!("Good evening!");
}

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@ -2,8 +2,6 @@
// Fill in the rest of the line that has code missing!
// No hints, there's no tricks, just get used to typing these :)
// I AM NOT DONE
fn main() {
// Characters (`char`)
@ -18,9 +16,9 @@ fn main() {
println!("Neither alphabetic nor numeric!");
}
let // Finish this line like the example! What's your favorite character?
// Try a letter, try a number, try a special character, try a character
// from a different language than your own, try an emoji!
let your_character = 'a'; // Finish this line like the example! What's your favorite character?
// Try a letter, try a number, try a special character, try a character
// from a different language than your own, try an emoji!
if your_character.is_alphabetic() {
println!("Alphabetical!");
} else if your_character.is_numeric() {

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@ -2,10 +2,8 @@
// Create an array with at least 100 elements in it where the ??? is.
// Execute `rustlings hint primitive_types3` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let a = ???
let a: [i8; 100] = [0; 100];
if a.len() >= 100 {
println!("Wow, that's a big array!");

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@ -2,13 +2,11 @@
// Get a slice out of Array a where the ??? is so that the test passes.
// Execute `rustlings hint primitive_types4` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[test]
fn slice_out_of_array() {
let a = [1, 2, 3, 4, 5];
let nice_slice = ???
let nice_slice = &a[1..a.len() - 1];
assert_eq!([2, 3, 4], nice_slice)
}

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@ -2,11 +2,9 @@
// Destructure the `cat` tuple so that the println will work.
// Execute `rustlings hint primitive_types5` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
fn main() {
let cat = ("Furry McFurson", 3.5);
let /* your pattern here */ = cat;
let (name, age) = cat;
println!("{} is {} years old.", name, age);
}

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@ -3,14 +3,11 @@
// You can put the expression for the second element where ??? is so that the test passes.
// Execute `rustlings hint primitive_types6` or use the `hint` watch subcommand for a hint.
// I AM NOT DONE
#[test]
fn indexing_tuple() {
let numbers = (1, 2, 3);
// Replace below ??? with the tuple indexing syntax.
let second = ???;
let second = numbers.1;
assert_eq!(2, second,
"This is not the 2nd number in the tuple!")
assert_eq!(2, second, "This is not the 2nd number in the tuple!")
}

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@ -4,11 +4,9 @@
// 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
let v = a.to_vec();
(a, v)
}

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@ -6,13 +6,9 @@
//
// 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].
@ -20,11 +16,13 @@ fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
}
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!
???
}).collect()
v.iter()
.map(|num| {
// TODO: Do the same thing as above - but instead of mutating the
// Vec, you can just return the new number!
2 * num
})
.collect()
}
#[cfg(test)]