Trie.rb

trie.rb

class Trie
  attr_accessor :hash, :value

  def initialize
    @hash = Array.new(26) { nil }
    @value = nil
  end

  def insert(new_word)
    word = new_word.downcase

    if !contains?(word)
      temp = self
      prev = self
      word.each_char do |c|
        prev = temp
        i = to_index(c)
        temp = @hash[i] || (@hash[i] = Trie.new)
      end

      prev.value = word
    end
  end

  def contains?(word)
    temp = self

    word.downcase!

    word.each_char do |c|
      i = to_index(c)
      if @hash[i].nil?
        return false
      else
        temp = @hash[i]
      end
    end

    temp.has_word?
  end

  def has_word?
    !value.nil?
  end

  def to_index(c)
    c.ord - 'a'.ord
  end

end


trie = Trie.new

p trie.insert("parrot")
p trie.insert("google")

p trie.contains?("facebook")
p trie.contains?("answer")
p trie.contains?("googl")
p trie.insert("monogram")
p trie.contains?("parrot")