freecodecamp--freecodecamp/curriculum/challenges/english/blocks/daily-coding-challenges-javascript/68ffb91507a5b645769328c7.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
68ffb91507a5b645769328c7	Challenge 104: Recipe Scaler	28	challenge-104

--description--

Given an array of recipe ingredients and a number to scale the recipe, return an array with the quantities scaled accordingly.

• Each item in the given array will be a string in the format: "quantity unit ingredient". For example "2 C Flour".
• Scale the quantity by the given number. Do not include any trailing zeros and do not convert any units.
• Return the scaled items in the same order they are given.

--hints--

scaleRecipe(["2 C Flour", "1.5 T Sugar"], 2) should return ["4 C Flour", "3 T Sugar"].

assert.deepEqual(scaleRecipe(["2 C Flour", "1.5 T Sugar"], 2), ["4 C Flour", "3 T Sugar"]);

scaleRecipe(["4 T Flour", "1 C Milk", "2 T Oil"], 1.5) should return ["6 T Flour", "1.5 C Milk", "3 T Oil"].

assert.deepEqual(scaleRecipe(["4 T Flour", "1 C Milk", "2 T Oil"], 1.5), ["6 T Flour", "1.5 C Milk", "3 T Oil"]);

scaleRecipe(["3 C Milk", "2 C Oats"], 0.5) should return ["1.5 C Milk", "1 C Oats"].

assert.deepEqual(scaleRecipe(["3 C Milk", "2 C Oats"], 0.5), ["1.5 C Milk", "1 C Oats"]);

scaleRecipe(["2 C All-purpose Flour", "1 t Baking Soda", "1 t Salt", "1 C Butter", "0.5 C Sugar", "0.5 C Brown Sugar", "1 t Vanilla Extract", "2 C Chocolate Chips"], 2.5) should return ["5 C All-purpose Flour", "2.5 t Baking Soda", "2.5 t Salt", "2.5 C Butter", "1.25 C Sugar", "1.25 C Brown Sugar", "2.5 t Vanilla Extract", "5 C Chocolate Chips"].

assert.deepEqual(scaleRecipe(["2 C All-purpose Flour", "1 t Baking Soda", "1 t Salt", "1 C Butter", "0.5 C Sugar", "0.5 C Brown Sugar", "1 t Vanilla Extract", "2 C Chocolate Chips"], 2.5), ["5 C All-purpose Flour", "2.5 t Baking Soda", "2.5 t Salt", "2.5 C Butter", "1.25 C Sugar", "1.25 C Brown Sugar", "2.5 t Vanilla Extract", "5 C Chocolate Chips"]);

--seed--

--seed-contents--

function scaleRecipe(ingredients, scale) {

  return ingredients;
}

--solutions--

function scaleRecipe(ingredients, scale) {
  return ingredients.map(item => {
    const [quantityStr, unit, ...rest] = item.split(" ");
    const ingredientName = rest.join(" ");
    
    const quantity = parseFloat(quantityStr) * scale;
    
    return `${quantity} ${unit} ${ingredientName}`;
  });
}