<codility> Frog Jump

frog_jump.rb

def solution(x, y, d)
  raise ArgumentError.new(
    "Invalid argument type"
  ) if !x.is_a?(Integer) || !y.is_a?(Integer)
  raise ArgumentError.new(
    "y should be less or equal to 1 000 000 000"
  ) if y > 1000000000
  raise ArgumentError.new(
    "x should be less then y and greater then 0"
  ) if x > y || x < 1

  ((y - x) / d*1.0).ceil
end

p solution(10, 85, 30)