36 lines
752 B
Ruby
36 lines
752 B
Ruby
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require 'prime'
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#1. generate quadratic expressions
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#2. for each quadratic expression, iterate until non-prime is found
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#3.
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def primes_from_quadratic(a,b)
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generator = Enumerator.new do |y|
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n = 0
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loop do
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y << n**2 + a*n + b
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n += 1
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end
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end
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primes = []
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while (next_num = generator.next).prime?
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primes << next_num
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end
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primes
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end
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max_consecutive_prime_length = 0
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max_consecutive_prime_coefficients = []
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(-999..999).each do |a|
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(-999..999).each do |b|
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prime_length = primes_from_quadratic(a,b).count
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if prime_length > max_consecutive_prime_length
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max_consecutive_prime_coefficients = [a,b]
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max_consecutive_prime_length = prime_length
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end
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end
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end
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puts max_consecutive_prime_coefficients
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