First attempt at ruby koans' Greed score calculator

gistfile1.rb

def score(dice)
  count_dice_types(dice).each_pair.inject(0) { |score, pair|
    value, count = pair
    score + score_dice_value(value, count)
  }
end

def score_dice_value(value, count)
  return 0 if count == 0
  return tripple_score(value) + score_dice_value(value, count - 3) if count > 2
  return 100 * count if value == 1
  return 50 * count if value == 5
  0
end

def tripple_score(value)
  return 1000 if value == 1
  value * 100
end

def count_dice_types(dice)
  dice.inject({}) { |counts, value|
    counts[value] = 0 if counts[value].nil?
    counts[value] += 1
    counts
  }
end