57 lines
1.2 KiB
Ruby
57 lines
1.2 KiB
Ruby
def gcd(a, b)
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b == 0 ? a : gcd(b, a % b)
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end
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def generate_fractional_pairs
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pairs = []
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(10..99).each do |i|
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(10..99).each do |j|
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pairs << [i,j] if i < j
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end
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end
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pairs
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end
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def check_weird_cancellations
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solutions = []
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fractions = generate_fractional_pairs
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fractions.each do |fraction|
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next if fraction.first % 10 == 0
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num = fraction.first.to_s
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den = fraction.last.to_s
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if (num.include?(den[0]))
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digit = num[num.index(den[0])]
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new_num = num.delete(digit)
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new_den = den.delete(digit)
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elsif (num.include?(den[1]))
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digit = num[num.index(den[1])]
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new_num = num.delete(digit)
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new_den = den.delete(digit)
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end
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solutions << [fraction.first, fraction.last] if (num.to_f / den.to_f) == (new_num.to_f / new_den.to_f)
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end
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solutions
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end
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def reduce_fraction(numerator, denominator)
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until (gcd = gcd(numerator, denominator)) == 1
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numerator /= gcd
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denominator /= gcd
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end
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[numerator, denominator]
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end
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def multiply_fractions(fractions)
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numerators = 1
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denominators = 1
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fractions.each do |fraction|
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numerators *= fraction.first
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denominators *= fraction.last
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end
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reduce_fraction(numerators, denominators)
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end
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