class DerivedClass < BaseClass
    #some stuff
end

class Creature
  def initialize(name)
    @name = name
  end
  
  def fight
    return "Punch to the chops!"
  end
end

# Add your code below!
class Dragon < Creature
    def fight
        return "Breathes fire!"
    end
end
    
dragon = Dragon.new("dragon")
dragon.fight
--------------------------------------------------
输出:
"Breathes fire!"

class DerivedClass < Base
  def some_method
    super(optional args)
      # Some stuff
    end
  end
end

class Creature
  def initialize(name)
    @name = name
  end
  
  def fight
    return "Punch to the chops!"
  end
end

# Add your code below!
class Dragon < Creature
    def fight
        puts "Instead of breathing fire..."
        super
    end
end
    
dragon = Dragon.new("w")
dragon.fight
-------------------------------------------------------------------
输出:
Instead of breathing fire...
"Punch to the chops!"

 1 class Person
 2   def initialize(name, age)
 3     @name = name
 4     @age = age
 5   end
 6   
 7   public    # This method can be called from outside the class.
 8   
 9   def about_me
10     puts "I'm #{@name} and I'm #{@age} years old!"
11   end
12   
13   private   # This method can't!
14   
15   def bank_account_number
16     @account_number = 12345
17     puts "My bank account number is #{@account_number}."
18   end
19 end
20 
21 eric = Person.new("Eric", 26)
22 eric.about_me
23 eric.bank_account_number  #错误, 调用了私有方法!
 -------------------------------------------------------------------------
 输出:
 I'm Eric and I'm 26 years old!
 private method `bank_account_number' called for #<Context::Person:0x0000000262d930 @name="Eric", @age=26>

def name
  @name
end

def name=(value)
  @name = value
end

class Person
  attr_reader :name
  attr_writer :name
  def initialize(name)
    @name = name
  end
end

def name
  @name
end

def name=(value)
  @name = value
end