#!/usr/bin/env ruby

def count_factors(n)
  count = 0
  c = 2
  while n > 1
    if n % c == 0
      n /= c
      count += 1
    else
      c += 1
    end
  end
  count
end

def prime_order(arr)
  arr.sort_by! do |a,b|
    fa = count_factors(a)
    fb = count_factors(b)
    fa == fb ? a <=> b : fa <=> fb
  end
end

arr = [11,8,27,4]
p prime_order(arr)