// We're collecting different fruits to bake a delicious fruit cake. For this, // we have a basket, which we'll represent in the form of a hash map. The key // represents the name of each fruit we collect and the value represents how // many of that particular fruit we have collected. Three types of fruits - // Apple (4), Mango (2) and Lychee (5) are already in the basket hash map. You // must add fruit to the basket so that there is at least one of each kind and // more than 11 in total - we have a lot of mouths to feed. You are not allowed // to insert any more of the fruits that are already in the basket (Apple, // Mango, and Lychee). use std::collections::HashMap; #[derive(Hash, PartialEq, Eq, Debug)] enum Fruit { Apple, Banana, Mango, Lychee, Pineapple, } fn fruit_basket(basket: &mut HashMap<Fruit, u32>) { let fruit_kinds = [ Fruit::Apple, Fruit::Banana, Fruit::Mango, Fruit::Lychee, Fruit::Pineapple, ]; for fruit in fruit_kinds { // If fruit doesn't exist, insert it with some value. basket.entry(fruit).or_insert(5); } } fn main() { // You can optionally experiment here. } #[cfg(test)] mod tests { use super::*; // Don't modify this function! fn get_fruit_basket() -> HashMap<Fruit, u32> { let content = [(Fruit::Apple, 4), (Fruit::Mango, 2), (Fruit::Lychee, 5)]; HashMap::from_iter(content) } #[test] fn test_given_fruits_are_not_modified() { let mut basket = get_fruit_basket(); fruit_basket(&mut basket); assert_eq!(*basket.get(&Fruit::Apple).unwrap(), 4); assert_eq!(*basket.get(&Fruit::Mango).unwrap(), 2); assert_eq!(*basket.get(&Fruit::Lychee).unwrap(), 5); } #[test] fn at_least_five_types_of_fruits() { let mut basket = get_fruit_basket(); fruit_basket(&mut basket); let count_fruit_kinds = basket.len(); assert!(count_fruit_kinds >= 5); } #[test] fn greater_than_eleven_fruits() { let mut basket = get_fruit_basket(); fruit_basket(&mut basket); let count = basket.values().sum::<u32>(); assert!(count > 11); } #[test] fn all_fruit_types_in_basket() { let fruit_kinds = [ Fruit::Apple, Fruit::Banana, Fruit::Mango, Fruit::Lychee, Fruit::Pineapple, ]; let mut basket = get_fruit_basket(); fruit_basket(&mut basket); for fruit_kind in fruit_kinds { let Some(amount) = basket.get(&fruit_kind) else { panic!("Fruit kind {fruit_kind:?} was not found in basket"); }; assert!(*amount > 0); } } }