balanced_tree.rb

# find if a tree is balanced
# i.e. no two nodes are more than 1 level away from root
# i.e. maxdepth - mindepth <= 1
def max_depth(root)
  return 0 if root.nil?
  return 1 + [max_depth(root.left) , max_depth(root.right)].max
end

def min_depth(root)
  return 0 if root.nil?
  return 1 + [min_depth(root.left), min_depth(root.right)].min
end

def is_balanced(root)
  puts max_depth(root)
  puts min_depth(root)
  return max_depth(root) - min_depth(root) <= 1
end