Daily Challenge #309 - Coffee Customization

You're an employee at a local cafe.

You can serve 3 coffee recipes:

• Black = Black Coffee
• Cubano = Cubano coffee + Brown sugar
• Americano = Americano coffee + Milk with 0.5% fat

... and you can add a lot of extra sugar and milk in any coffee, for example:

• Black coffee + Milk with 3.2% fat + Brown sugar
• Cubano coffee + Brown sugar + Brown sugar + Cane sugar
• Americano coffee + Milk with 3.2% fat + Cane sugar

With the following code provided for you, can you create a Coffee by implementing a CoffeeBuilder struct/class?

You can start from scratch or use the following code as a starting off point:

C++
struct Milk {
  float fat;
};

struct Sugar {
  std::string sort;
};

struct Coffee {
  std::string sort;
  std::vector<Milk> milk;
  std::vector<Sugar> sugar;
};

Rust
#[derive(Debug)]
struct Coffee {
    sort: String,
    milk: Vec<Milk>,
    sugar: Vec<Sugar>,
}

#[derive(Debug)]
struct Milk {
    fat: f32,
}

#[derive(Debug)]
struct Sugar {
    sort: String,
}

struct CoffeeBuilder {
    sort: String,
    milk: Vec<Milk>,
    sugar: Vec<Sugar>,
}

Tests

1. A Black coffee with sugar and milk with 3.2% fat, please.
2. A Cubano coffee, please.
3. An Americano with two brown sugars, please.

Good luck!

---

This challenge comes from arkada38 on CodeWars. Thank you to CodeWars, who has licensed redistribution of this challenge under the 2-Clause BSD License!

Want to propose a challenge idea for a future post? Email [e-mail] with your suggestions!

Comments

[Amin]

JavaScript

const count = (count, item) => ({ ...count, [item]: (count[item] || 0) + 1 });
const announce = callback => (announcements, [item, count]) => [...announcements, callback(item, count)];
const pluralize = (count, text) => count > 1 ? `${text}s` : text;
const coffee = (kind, sugars = [], milks = []) => ({
  addSugar: sugar => coffee(kind, [...sugars, sugar]),
  addMilk: milk => coffee(kind, sugars, [...milks, milk]),
  announce: () => {
    const sugarCount = sugars.reduce(count, {});
    const sugarAnnouncement = Object.entries(sugarCount).reduce(announce((sugar, count) => `with ${count} ${sugar} ${pluralize(count, "sugar")}`), []);
    const milkCount = milks.reduce(count, {});
    const milkAnnouncement = Object.entries(milkCount).reduce(announce((fat, count) => `with ${count} ${fat}% fat ${pluralize(count, "milk")}`), []);
    const announcements = [...sugarAnnouncement, ...milkAnnouncement];
    return announcements.length > 0 ? `One ${kind} ${announcements.join(", ")}, please.` : `One ${kind}, please.`;
  }
});

Usage

const firstOrder = 
  coffee("black coffee")
    .addSugar("regular")
    .addMilk(3.2)
    .announce();

const secondOrder = coffee("Cubano coffee").announce();

const thirdOrder = 
  coffee("Americano")
    .addSugar("brown")
    .addSugar("brown")
    .announce();

console.log(firstOrder);  // One black coffee with 1 regular sugar, with 1 3.2% fat milk, please.
console.log(secondOrder); // One Cubano coffee, please.
console.log(thirdOrder);  // One Americano with 2 brown sugars, please.

[Mihail Malo]

Not gonna lie,

struct Milk {
    fat: f32,
}

got me giggling