Extreme

gistfile1.rb

def average(array)
  array.inject(0) { |memo, element| memo += element } / array.size
end

def calculate_deviation(value, average)
  value >= 0 ? value - average : average - value
end

def solution(a)
  extreme_element_index = -1
  average = average(a)
  a.each_with_index.inject(nil) do |highest_deviation, (element, index)|
    deviation = calculate_deviation(element, average)
    if deviation > average
      if extreme_element_index != -1
        if deviation > highest_deviation
          highest_deviation = deviation
          extreme_element_index = index
        end
      else
        highest_deviation = deviation
        extreme_element_index = index
      end
    end
    highest_deviation
  end
  extreme_element_index
end


a = [9,4,-3,-10]

puts solution(a)