euler/euler035.rb

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Ruby
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require 'prime'
def primes_up_to(n)
Prime.take_while { |x| x < n }
end
def integer_rotations(n)
rotations = []
digits = n.to_s.split('')
digits.count.times do
rotations << digits.join('').to_i
digits.rotate!
end
rotations
end
def is_circular?(n)
circular = true
integer_rotations(n).each do |perm|
return false unless Prime.prime?(perm)
end
circular
end
def circular_primes_up_to(n)
primes_up_to(n).select { |x| puts x; is_circular?(x) }
end