Ruby:获取最大值的哈希对

Question

这是一个哈希,记录我有多少水果

fruits = {"apples" => 10, "pears" => 15, "bananas" => 15, "grapes" => 12}

而且我想知道我最常吃的是哪种水果.
如果有断路器,那么就把它们全部归还.

Answer 1

# easy
max_quantity = fruits.values.max
max_fruits = fruits.select { |k, v| v == max_quantity }.keys

# fast                                                                          
max_quantity = -1.0/0.0
max_fruits = []
fruits.each do |k, v|
  if v > max_quantity
    max_quantity = v
    max_fruits = []
  end
  max_fruits.push k if v == max_quantity
end

由于异常情况为Bad(tm),因此这两种情况总是返回一个数组.

Answer 2

max_value = fruits.values.max
keys = fruits.select{|k, v| v == max_value}.keys