Linked List

linked_list.rb

class Node
  attr_accessor :next, :value
  def initialize(value)
    @value = value
  end
end

class LinkedList
  attr_accessor :tail, :head

  def initialize(head)
    @head = head
    @tail = head
  end

  def push(node)
    @tail.next = node
    @tail = node
  end

  def each(&block)
    next_node = @head
    until (next_node == nil) do
      block.call(next_node)
      next_node = next_node.next
    end
  end

  def reverse_list!(curr=@head)
    return curr if curr == nil or curr.next == nil
    next_node = curr.next
    new_head = reverse_list!(curr.next)
    next_node.next = curr
    curr.next = nil
    self.head = new_head
    return new_head
  end
end


head = Node.new(0)

linked_list = LinkedList.new(head)
(1..5).each {|value| linked_list.push(Node.new(value)) }

linked_list.each{|x|p x.value unless x == nil}

linked_list.reverse_list!()

linked_list.each{|x|p x.value unless x == nil}