Square_every_digit.rb

# question
# Welcome. In this kata, you are asked to square every digit of a number.
# For example, if we run 9119 through the function, 811181 will come out.
# Note: The function accepts an integer and returns an integer

def square_digits(num)
  num.to_s.chars.map{|n| n.to_i ** 2 }.join.to_i
end

# test
puts square_digits(6414)