Ruby Koans 计分项目

Question

我正在研究 Ruby Koans，我在弄清楚我编写的方法出了什么问题时遇到了一些麻烦。我在about_scoring_project.rb中，写了骰子游戏的计分方法:

def score(dice)
  return 0 if dice == []
  sum = 0
  rolls = dice.inject(Hash.new(0)) { |result, element| result[element] += 1; result; }
  rolls.each { |key, value| 
    # special condition for rolls of 1
    if key == 1  
      sum += 1000 | value -= 3 if value >= 3
      sum += 100*value
      next
    end
    sum += 100*key | value -= 3 if value >= 3
    sum += 50*value if key == 5 && value > 0
  }
  return sum
end

对于那些不熟悉这个练习的人:

Greed is a dice game where you roll up to five dice to accumulate points. The following "score" function will be used to calculate the score of a single roll of the dice.

A greed roll is scored as follows:

• A set of three ones is 1000 points

• A set of three numbers (other than ones) is worth 100 times the number. (e.g. three fives is 500 points).

• A one (that is not part of a set of three) is worth 100 points.

• A five (that is not part of a set of three) is worth 50 points.

• Everything else is worth 0 points.

Examples:

score([1,1,1,5,1]) => 1150 points score([2,3,4,6,2]) => 0 points score([3,4,5,3,3]) => 350 points score([1,5,1,2,4]) => 250 points

More scoring examples are given in the tests below:

Your goal is to write the score method.

当我尝试运行文件中的最后一个测试时遇到了麻烦:assert_equal 550, score([5,5,5,5])

出于某种原因，我返回 551 而不是 550。感谢您的帮助!

Answer 1

这是我的方法:

def score(dice)
  # Count how many what
  clusters = dice.reduce(Hash.new(0)) {|hash, num| hash[num] += 1; hash }

  # Since 1's are special, handle them first
  ones = clusters.delete(1) || 0
  score = ones % 3 * 100 + ones / 3 * 1000

  # Then singular 5's
  score += clusters[5] % 3 * 50

  # Then the triples other than triple-one
  clusters.reduce(score) {|s, (num, count)| s + count / 3 * num * 100 }
end