(define (find-closest-number goal numbers)
   (if (= 1 (length numbers))
       (car numbers)
       (if (< (abs (- goal (car numbers)))
              (abs (- goal 
                      (find-closest goal (cdr numbers)))))
           (car numbers)
           (find-closest goal (cdr numbers)))))

(define (find-closest goal lst comparator)
  (if (= 1 (length lst))
      (car lst)
      (if (< (comparator goal (car lst))
             (comparator goal 
                         (find-closest goal (cdr lst) comparator)))
          (car lst)
          (find-closest goal (cdr lst) comparator))))

(define (find-closest-number2 goal numbers)
  (find-closest goal numbers (lambda (a b) (abs (- a b)))))

(define (find-closest-below goal numbers)
  (find-closest goal numbers (lambda (a b) (if (>= a b) (- a b) 99999))))

(define (list-or-not-cruncher base nonlist
                              proc combiner lst)
  (if (null? lst)
      base
      (if (not (pair? lst))
          nonlist
          (combiner (proc (car lst))
                    (list-or-not-cruncher base nonlist proc combiner 
                                          (cdr lst))))))

(define (list? p)
  (list-or-not-cruncher 
   #t #f (lambda (x) x) (lambda (f r) r) p))
  

(define (pick-closest closeness goal num1 num2)
   (if (< (closeness goal num1)
            (closeness goal num2))
       num1
       num2))

(define (find-closest goal lst closeness)
   (if (= 1 (length lst))
 (car lst)
 (pick-closest closeness goal (car lst) 
		     (find-closest goal (cdr lst) closeness))))