NoMethodError while adding node in Ruby-CodePudding

I am trying to print a linked list in ruby but getting the error add': undefined method `next=' for #<Node:0x000001c5c0738688 @data=1, @next=nil> (NoMethodError) any idea what i should do ?

class Node
    def initialize data
        @data = data
        @next = nil
    end
end

class LinkedList
    def initialize
        @head = nil
    end
    def add data
        temp = @head
        @head = Node.new(data)
        @head.next = temp
    end
    def printList
        temp = @head
        while temp
            puts temp.data
            temp = temp.next
        end
    end
end

list = LinkedList.new
list.add(1)
list.add(2)
list.add(3)

list.printList()

CodePudding user response：

In order to access the setter for the next attribute I'd propose adding an attribute_accessor to Node.

class Node
  attr_accessor :next

  def initialize(data)
    @data = data
  end
end

This will generate both a setter and a getter for the next attribute within your Node instance.

Additionally I would also add an attr_reader to Node so that you can access data from outside of the instance.

class Node
  attr_accessor :next
  attr_reader :data

  def initialize(data)
    @data = data
  end
end