[Solved] What will be the output of this Ruby code?class Dog @@count = 0 def initialize @@count += 1 end def self.count @@count end end Dog.new Dog.new puts Dog.count | Ruby

Ruby - Class Methods and Variables

What will be the output of this Ruby code?

class Dog
  @@count = 0
  def initialize
    @@count += 1
  end
  def self.count
    @@count
  end
end

Dog.new
Dog.new
puts Dog.count

A2

B0

C1

DError

Step-by-Step Solution

Solution:

Step 1: Understand class variable usage
@@count is a class variable shared by all Dog instances. It starts at 0.
Step 2: Count increments on each new Dog
Each Dog.new calls initialize, which adds 1 to @@count. Two Dog.new calls increase @@count to 2.
Step 3: Output the class variable
Dog.count returns @@count, which is 2, so puts prints 2.
Final Answer:
2 -> Option A
Quick Check:
Class variable increments twice = 2 [OK]

Quick Trick: Class variables track shared data across all instances [OK]

Common Mistakes:

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