How can I check is a number is a Dudeney Number, using Ruby? -

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how can check if number dudeney number, using ruby? taking examples or evidence, these results:

dudeney_number?(1)     #=> true dudeney_number?(125)   #=> false dudeney_number?(512)   #=> true dudeney_number?(1728)  #=> false dudeney_number?(5832)  #=> true

from https://en.wikipedia.org/wiki/dudeney_number:

a dudeney number positive integer perfect cube such sum of decimal digits equal cube root of number.

here's implementation definition:

def dudeney_number?(n)   digit_sum = n.to_s.chars.map(&:to_i).inject(:+)   n == digit_sum ** 3 end  1.upto(20000).select { |n| dudeney_number? n } #=> [1, 512, 4913, 5832, 17576, 19683]

the method doesn't check if n positive integer.


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