Check for continuous binary tree in ruby

Ruby program for Check for continuous binary tree. Here problem description and explanation.

#  Ruby program for
#  Check if binary tree is continuous tree
#  Using recursion

#  Binary Tree Node
class TreeNode 
	# Define the accessor and reader of class TreeNode
	attr_reader :data, :left, :right
	attr_accessor :data, :left, :right
	def initialize(data) 
		#  Set node value
		self.data = data
		self.left = nil
		self.right = nil
	end

end

class BinaryTree 
	# Define the accessor and reader of class BinaryTree
	attr_reader :root
	attr_accessor :root
	def initialize() 
		self.root = nil
	end

	def absValue(num) 
		if (num < 0) 
			return -num
		end

		return num
	end

	#  Check tree is continuous or not
	def isContinuous(node) 
		if (node != nil) 
			if ((node.left != nil && 
                 self.absValue(node.data - node.left.data) != 1) || 
                (node.right != nil && 
                 self.absValue(node.data - node.right.data) != 1)) 
				#  Case
				#  When fail continuous tree rule
				return false
			end
			if (self.isContinuous(node.left) && 
                self.isContinuous(node.right)) 
				return true
			end
			#  When node value is not satisfied
			#   continuous tree properties
			return false
		end
		return true
	end
end

def main() 
	#  Create new tree
	tree = BinaryTree.new()
	#   Binary Tree
	#   ------------
	#       5
	#     /   \
	#    4     4
	#   /     /  \
	#  3     5    3
	#   \
	#    2
	#  Add tree node
	tree.root = TreeNode.new(5)
	tree.root.left = TreeNode.new(4)
	tree.root.right = TreeNode.new(4)
	tree.root.left.left = TreeNode.new(3)
	tree.root.right.right = TreeNode.new(3)
	tree.root.right.left = TreeNode.new(5)
	tree.root.left.left.right = TreeNode.new(2)
	if (tree.isContinuous(tree.root) == true) 
		print("Continuous Tree \n")
	else
		print("Not Continuous Tree \n")
	end

	#  Case 2
	#       5
	#     /   \
	#    4     4
	#   /     /  \
	#  3     5    3
	#   \
	#    1  <--- change value
	tree.root.left.left.right.data = 1
	if (tree.isContinuous(tree.root) == true) 
		print("Continuous Tree \n")
	else
		print("Not Continuous Tree \n")
	end
end

main()

Output

Continuous Tree 
Not Continuous Tree