linked_list_removeAt.rb

def removeAt(index)
  prev = nil
  node = @head
  i = 0
  loop do
    prev = node
    node = node.next
    i += 1
    break unless !node.nil? and i < index
  end
  if prev.nil?
    @head = node.next
  else
    prev.next = node.next
  end
end