e62.rb

def euler_62
  n = 1
  hash = Hash.new {|h, k| h[k] = []}
  current_length = 1
  while true
    cubic = n**3
    key = cubic.to_s.split('').sort.join
    hash[key] << cubic

    if key.length > current_length
      current_length = key.length
      r = hash.values.find_all {|v| v.length == 5}.flatten.min
      break r if r
    end
    n += 1
  end
end

p euler_62