Day13 - Abstract Classes (Python 3)

• URL : https://www.hackerrank.com/challenges/30-abstract-classes/problem

• Objective
  • Today, we’re taking what we learned yesterday about Inheritance and extending it to Abstract Classes. Because this is a very specific Object-Oriented concept, submissions are limited to the few languages that use this construct. Check out the Tutorial tab for learning materials and an instructional video!
• Task
  • Given a Book class and a Solution class, write a MyBook class that does the following:
  • Inherits from Book
  • Has a parameterized constructor taking these 3 parameters:
    • string title
    • string author
    • int price
  • Implements the Book class’ abstract display() method so it prints these 3 lines:
    • title, a space, and then the current instance’s title.
    • author, a space, and then the current instance’s author.
    • price, a space, and then the current instance’s price.

• Note: Because these classes are being written in the same file, you must not use an access modifier (e.g.:pubilc ) when declaring MyBook or your code will not execute.

• Input Format
  • You are not responsible for reading any input from stdin. The Solution class creates a Book object and calls the MyBook class constructor (passing it the necessary arguments). It then calls the display method on the Book object.
• Output Format

  • The void display() method should print and label the respective title, author, and price of the MyBook object’s instance (with each value on its own line) like so:

    • Title: $title
    • Author: $author
    • Price: $price
• Note: The & is prepended to variable names to indicate they are placeholders for variables.

문제풀이

• Book이라는 클래스를 상속받을떄 추상클래스를 생성하는것
• 아래에서는 Book에서는 타이틀, 작가를 받는데, MyBook는 타이틀, 작가, 가격까지 받음
• 이후 display라는 메서드로 입력받은 내용을 출력해주면 됨

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from abc import ABCMeta, abstractmethod
class Book(object, metaclass=ABCMeta):
    def __init__(self,title,author):
        self.title=title
        self.author=author   
    @abstractmethod
    def display(): pass

#Write MyBook class
class MyBook(Book):
    def __init__(self, title, author, price):
        self.title = title
        self.author = author
        self.price = price

    def display(self):
        print('Title:', self.title)
        print('Author:', self.author)
        print('Price:',  self.price)

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title=input()
author=input()
price=int(input())
new_novel=MyBook(title,author,price)
new_novel.display()

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 해리포터
 존레논
 30000


Title: 해리포터
Author: 존레논
Price: 30000