ex.rb

class Road
  attr_accessor :low_bound,
                :high_bound,
                :transport_count,
                :road_id

end

r = Road.new
r.road_id = 1

r1 = Road.new
r1.road_id = 2

arr = Array.new

arr << r
arr << r1

i = 0
while i < 10
  arr[i / 2].transport_count += 1
end