Project Euler Problem 1

project_euler_1.rb

# solves http://projecteuler.net/problem=1
# not the shortest solution, but one with a more versatile and reusable method

def divisibles(up_to, divisible_by_a, divisible_by_b)
    rangeArray = (1..(up_to -1)).to_a
    just_multiples = []
    rangeArray.each do |x|
        if ( x % divisible_by_a == 0 || x % divisible_by_b == 0 )
            just_multiples << x
        end
    end
    just_multiples.inject { |x, sum| sum + x }
end

divisibles(1000, 3, 5)
# => 233168