I'm having issues understanding this encapsulation. I have instance variables defined with attr_accessor. I'm trying to access them outside class. But they are always nil and returns undefined method.
NoMethodError: undefined method `has_key?' for nil:NilClass
Please help me understand.
class TrieNode
attr_reader :value, :next, :children
def initalize
@value = nil
@children = Hash.new
@next = nil
end
end
class Trie
attr_accessor :root
def initialize
@root = TrieNode.new
end
def build_trie(strs)
cur = @root
strs.each do |str|
str.chars.each do |char|
if cur.children.has_key? char
cur = cur.children[char]
next
else
new_node = TrieNode.new
cur.children[char] = new_node
cur = new_node
end
end
cur = @root
end
end
end
