مخزون المتجر

fibonacci = [0, 1, 1, 2, 3, 5, 8, 13]

fibonacci.count  { |number| number == 1 }   #=> 2
fibonacci.any?   { |number| number > 20 }   #=> false
fibonacci.none?  { |number| number > 20 }   #=> true
fibonacci.select { |number| number.odd? }   #=> [1, 1, 3, 5, 13]
fibonacci.all?   { |number| number < 20 }   #=> true
fibonacci.map    { |number| number * 2  }   #=> [0, 2, 2, 4, 6, 10, 16, 26]
fibonacci.select { |number| number >= 5 }   #=> [5, 8, 13]
fibonacci.find   { |number| number >= 6 }   #=> 8

# Some methods work with or without a block
fibonacci.sum  #=> 33
fibonacci.sum { |number| number * number }  #=> 273

# There are also methods to help with nested arrays:
animals = [ ['cat', 'bob'], ['horse', 'caris'], ['mouse', 'arya'] ]
animals.flatten  #=> ["cat", "bob", "horse", "caris", "mouse", "arya"]

pet_names = {cat: "bob", horse: "caris", mouse: "arya"}
pet_names.each { |animal, name| ... }

pet_names = {cat: "bob", horse: "caris", mouse: "arya"}
pet_names.map { |_, name| name }  #=> ["bob", "caris", "arya"]

pets = [
  { animal: "cats", names: ["bob", "fred", "sandra"] },
  { animal: "horses", names: ["caris", "black beard", "speedy"] },
  { animal: "mice", names: ["arya", "jerry"] }
]

pets.map { |pet|
  pet[:names].select { |name| name.length <= 5 }
}.flatten.sort
#=> ["arya", "bob", "caris", "fred", "jerry"]

التعليمات

أنت تدير متجر أزياء على الإنترنت. اقترب موعد تخفيضاتك السنوية الكبرى، لذلك تريد إنشاء بعض الوظائف التي تساعدك على جرد مخزونك والتأكد من أنك مستعد.

يُمثَّل كل عنصر في المخزون بقيمة hash، والمخزون بأكمله مصفوفة من هذه الـ hash.

[
  {
    name: "White Shirt",
    price: 40,
    quantity_by_size: {s: 3, m: 7, l: 8, xl: 4}
  },
  { ... }
]

1. أرجع قائمة بأسماء العناصر

نفّذ BoutiqueInventory.item_names، التي يجب أن تُرجع قائمة بأسماء العناصر مرتبة أبجديًا.

BoutiqueInventory.new([
  {price: 65.00, name: "Maxi Brown Dress", quantity_by_size: {s: 3, m: 7, l: 8, xl: 4}},
  {price: 50.00, name: "Red Short Skirt", quantity_by_size: {}},
  {price: 29.99, name: "Black Short Skirt", quantity_by_size: {s: 1, xl: 4}},
  {price: 20.00, name: "Bamboo Socks Cats", quantity_by_size: {s: 7, m: 2}}
]).item_names

#=> ["Bamboo Socks Cats", "Black Short Skirt", "Maxi Brown Dress", "Red Short Skirt"]

2. أرجع العناصر الرخيصة

نفّذ BoutiqueInventory.cheap، التي يجب أن تُرجع العناصر التي يقل سعرها عن 30 دولارًا.

BoutiqueInventory.new([
  {price: 65.00, name: "Maxi Brown Dress", quantity_by_size: {s: 3, m: 7, l: 8, xl: 4}},
  {price: 50.00, name: "Red Short Skirt", quantity_by_size: {}},
  {price: 29.99, name: "Black Short Skirt", quantity_by_size: {s: 1, xl: 4}},
  {price: 20.00, name: "Bamboo Socks Cats", quantity_by_size: {s: 7, m: 2}}
]).cheap

# => [
#      {price: 29.99, name: "Black Short Skirt", quantity_by_size: {s: 1, xl: 4}},
#      {price: 20.00, name: "Bamboo Socks Cats", quantity_by_size: {s: 7, m: 2}}
#    ]

3. أرجع العناصر التي نفد مخزونها

نفّذ BoutiqueInventory.out_of_stock، التي يجب أن تُرجع العناصر التي لا يتوفر لها أي مخزون (حيث تكون quantity_by_size فارغة).

BoutiqueInventory.new([
  {price: 65.00, name: "Maxi Brown Dress", quantity_by_size: {s: 3, m: 7, l: 8, xl: 4}},
  {price: 50.00, name: "Red Short Skirt", quantity_by_size: {}},
  {price: 29.99, name: "Black Short Skirt", quantity_by_size: {s: 1, xl: 4}},
  {price: 20.00, name: "Bamboo Socks Cats", quantity_by_size: {s: 7, m: 2}}
]).out_of_stock

#=> [{price: 50.00, name: "Red Short Skirt", quantity_by_size: {}}]

4. أرجع مخزون عنصر واحد

نفّذ BoutiqueInventory.stock_for_item(name) لتُرجع مخزون عنصر ما باسمه:

BoutiqueInventory.new([
  {price: 65.00, name: "Maxi Brown Dress", quantity_by_size: {s: 3, m: 7, l: 8, xl: 4}},
  {price: 50.00, name: "Red Short Skirt", quantity_by_size: {}},
  {price: 29.99, name: "Black Short Skirt", quantity_by_size: {s: 1, xl: 4}},
  {price: 20.00, name: "Bamboo Socks Cats", quantity_by_size: {s: 7, m: 2}}
]).stock_for_item("Black Short Skirt")

#=> {s: 1, xl: 4}

5. أرجع إجمالي المخزون

نفّذ BoutiqueInventory.total_stock لحساب إجمالي عدد العناصر في مخزنك:

BoutiqueInventory.new([
  {price: 65.00, name: "Maxi Brown Dress", quantity_by_size: {s: 3, m: 7, l: 8, xl: 4}},
  {price: 50.00, name: "Red Short Skirt", quantity_by_size: {}},
  {price: 29.99, name: "Black Short Skirt", quantity_by_size: {s: 1, xl: 4}},
  {price: 20.00, name: "Bamboo Socks Cats", quantity_by_size: {s: 7, m: 2}}
]).total_stock

#=> 36