(define (divides x y)
  (= (remainder y x) 0))
(define (LEAP-YEAR x)
  (if (divides 4 x)
      (if (divides 100 x)
        (if (divides 400 x)
          #t
          #f)
        #t)
      #f))
(define (LEAP-YEAR-2 x)
  (and (divides 4 x) (or (not (divides 100 x)) (divides 400 x))))