Question

I’m trying to randomly generate two integers that add up to a previously selected integer.

For instance, if I have a previously selected value of 12, I need a method that could generate [6,6], or [11,1], etc.

Answer 1

Edit: see this answer

Just for fun (I’m sure it’s not 100% for negatives etc…) :

class Fixnum
  def rand_sum(n = 2)
    arr = (n - 1).times.reduce([]) do |a, _|
      curr_max = self - a.reduce(0, :+)
      a << rand(0..curr_max)
    end

    arr << self - arr.reduce(0, :+)
  end
end

 11.rand_sum
 => [6, 5] 
 23.rand_sum 3
 => [10, 6, 7] 
 11.rand_sum 3
 => [6, 2, 3]