# CSE341, Spring 2008, Homework 6 provided code

# Put your solutions to problems 1--4 here

# A few tests for the trees, not necessarily meant to cover everything

def test_tree
  t1 = Leaf.new "hi"
  t1a = Leaf.new "there"
  t2 = NaryNode.new([t1a, (Leaf.new "world")])
  t3 = BinaryNode.new(t1,t2)
  puts t3.concatAll
  puts t3.firstAlphabetical
  t3.iterate(lambda { |s| puts s })
  puts (BinaryNode.concatAll t3)

  puts "======" # below here works only after problem 3

  t1 = "hi"
  t1a = "there"
  t2 = NaryNode.new([t1a, ("world")])
  t3 = BinaryNode.new(t1,t2)
  puts t3.concatAll
  puts t3.firstAlphabetical

end

# The rest of the file is for problem 5

class LetterCount
  attr_reader :hash
  protected :hash
  def initialize arg
    if arg.is_a? String
      @hash = str_to_count arg
    elsif arg.is_a? Hash
      @hash = arg
    else
      raise "bad argument"
    end
  end
  def difference other
    ans = @hash.clone
    other.hash.each { |letter, value| 
      if value > ans[letter] 
        return nil 
      else 
        ans[letter] -= value
      end
    }
    LetterCount.new ans
  end
  def all_zeros 
    @hash.each { |letter,value| if value != 0 : return false end }
    true
  end

private
  def str_to_count s
    h = Hash.new 0
    s.split("").each { |c| h[c] += 1 }
    h
  end
end

def anagrams(word,filename)
  lc = LetterCount.new word
  file = File.new(filename, "r")
  file.each_line { |w|
    w = w.chop
    wlc = LetterCount.new w
    d = lc.difference wlc
    if d && d.all_zeros then puts w end
  }
  file.close
end