32 lines
627 B
Ruby
32 lines
627 B
Ruby
require 'prime'
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def d(n)
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divisors = [1]
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(2..Math.sqrt(n)).each do |possible_divisor|
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if n % possible_divisor == 0
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divisors << possible_divisor
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divisors << (n / possible_divisor)
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end
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end
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divisors.inject(:+)
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end
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def amicable_numbers(n)
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d_values = {}
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(2..n).each do |num|
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d_values[num] = d(num)
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end
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possible_amicables = d_values.select{ |key, value| value <= n }
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amicables = []
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possible_amicables.each do |key, value|
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if d_values[value] == key && key != value
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amicables << [key, value]
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end
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end
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amicables.flatten.uniq
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end
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puts amicable_numbers(100000).inject(:+)
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