10 lines
213 B
Ruby
10 lines
213 B
Ruby
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require 'prime'
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def pandigital?(n)
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n.to_s.split('').map(&:to_i).sort == (1..n.to_s.length).to_a
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end
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def largest_pandigital_prime_up_to(n)
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Prime.take_while { |i| i < n }.select { |i| pandigital?(i) }.max
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end
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