solved primitive types, vecs and ifs

This commit is contained in:
Richard Hoffmann 2023-07-15 21:23:27 +02:00
parent 50b048d6c1
commit bd36552e2f
11 changed files with 34 additions and 42 deletions

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@ -1,9 +1,12 @@
// 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 {
if a > b {
a
} else {
b
}
// Complete this function to return the bigger number!
// Do not use:
// - another function call

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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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@ -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: bool = false; // 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`)
@ -18,7 +16,7 @@ fn main() {
println!("Neither alphabetic nor numeric!");
}
let // Finish this line like the example! What's your favorite character?
let your_character: char = '8'; // 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() {

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@ -2,10 +2,9 @@
// 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: [i32; 200] = [0; 200];
// let a = Vec::from_iter([0..200]);
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..4];
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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@ -10,10 +10,14 @@
// Write a function that calculates the price of an order of apples given
// the quantity bought. No hints this time!
// I AM NOT DONE
// Put your function here!
// fn calculate_price_of_apples {
fn calculate_price_of_apples(num: i32) -> i32 {
if num > 40 {
num
} else {
num * 2
}
}
// Don't modify this function!
#[test]

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@ -4,12 +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 = vec![10, 20, 30, 40];
(a, v)
}

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@ -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 element in v.iter_mut() {
// TODO: Fill this up so that each element in the Vec `v` is
// multiplied by 2.
???
*element = *element * 2;
}
// At this point, `v` should be equal to [4, 8, 12, 16, 20].
@ -20,11 +18,13 @@ fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
}
fn vec_map(v: &Vec<i32>) -> Vec<i32> {
v.iter().map(|element| {
v.iter()
.map(|element| {
// TODO: Do the same thing as above - but instead of mutating the
// Vec, you can just return the new number!
???
}).collect()
element * 2
})
.collect()
}
#[cfg(test)]