timesink.rb

# If we list all the natural numbers below 10 that are multiples of 3 or 5, 
# we get 3, 5, 6 and 9. The sum of these multiples is 23. 
# Find the sum of all the multiples of 3 or 5 below 1000.

class MulitpleSum

  attr_reader :target, :dividers

  def initialize(target:, dividers:[])
    @target = target
    @dividers = dividers
  end

  def sum
    (0...target).map { |x| x if modulus?(x) }.compact.inject(&:+)
  end

  def modulus?(x)
    dividers.map{ |y| x % y == 0 }.any?{ |x| x == true }
  end

end

p MulitpleSum.new(target: 1000, dividers: [3,5]).sum # 233168