Trie Implementation in Ruby

trie.rb

# Meant for strings consisting of English characters.

class TrieNode
	attr_accessor :terminal, :character

	def initialize(character: "", terminal: false)
		@character = character
		@terminal = terminal
		@children = []
	end

	def add_node(node)
		i = node.character.ord % 97
		@children[i] = node
	end

	def next_node(character)
		i = character.ord % 97
		@children[i]
	end
end

class Trie
	def initialize
		@root = TrieNode.new
	end

	def word_present?(word)
		current_node = @root
		word.chars.each do |c|
			unless current_node = current_node.next_node(c)
				return nil
			end
		end
		current_node.terminal
	end

	def add_word(word)
		current_node = @root
		word.chars.each do |c|
			if current_node.next_node(c)
				current_node = current_node.next_node(c)
			else
				new_node = TrieNode.new(character: c)
				current_node.add_node(new_node)
				current_node = new_node
			end
		end
		current_node.terminal = true
	end
end