binary tree example for WDI-SF-MAY

binary_tree.rb

require "pry"
require "pry-debugger"
require "pry-stack_explorer"


class Node
  attr_accessor :data, :nxt, :prv

  def initialize(data)
    self.data = data
    self.nxt = nil
    self.prv = nil
  end

  def to_s
    "prev:#{!self.prv.nil? ? self.prv.data : 'nil'} - #{self.data} - next:#{!self.nxt.nil? ? self.nxt.data : 'nil'}"
  end
end


class Tree
  attr_accessor :root

  def insert(new_node, r=self.root)
    if self.root.nil?
      self.root = new_node
    else
      if r.data < new_node.data
        if r.nxt.nil?
          r.nxt = new_node
        else
          insert(new_node, r.nxt)
        end
      else
        if r.prv.nil?
          r.prv = new_node
        else
          insert(new_node, r.prv)
        end
      end
    end
  end

  def find(name, r=self.root)
    if r.data == name
      return r
    else
      if r.data > name
        if r.prv.nil?
          puts "not found"
        else
          find(name, r.prv)
        end
      else
        if r.nxt.nil?
          puts "not found"
        else
          find(name, r.nxt)
        end
      end
    end
  end

  def to_s
    if self.root.nil?
      "empty"
    else
      tree_list(self.root)
    end
  end

  def tree_list(node)
    name_list = []
    if !node.prv.nil?
      name_list << tree_list(node.prv)
    end
    name_list << node.data
    if !node.nxt.nil?
      name_list << tree_list(node.nxt)
    end
    return name_list
  end
end