Рекурсия, необходим совет

(defun sum-m-p (w &optional (m 0) (p 0))
  (cond ((null w) (list m p))
        ((minusp (car w)) (sum-m-p (cdr w) (+ m (car w)) p))
        (t (sum-m-p (cdr w) m (+ p (car w))))))
 
> (sum-m-p '(-3 -2 -1 0 1 2 3))
(-6 6)

(defun sum-m-p (w) (sum w 0 0))
 
(defun sum (w m p)
  (cond ((null w) (list m p))
        ((minusp (car w)) (sum (cdr w) (+ m (car w)) p))
        (t (sum (cdr w) m (+ p (car w))))))
 
> (sum-m-p '(-3 -2 -1 0 1 2 3))
(-6 6)

(defun sum-m-p (w) (sum w 0 0))
 
(defun sum (w m p)
  (cond ((null w) (values m p))
        ((minusp (car w)) (sum (cdr w) (+ m (car w)) p))
        (t (sum (cdr w) m (+ p (car w))))))
 
> (sum-m-p '(-3 -2 -1 0 1 2 3))
-6
6

(defun sum-m-p (w) (sum w 0 0))
 
(defun sum (w m p)
  (if w
      (if (minusp (car w))
          (sum (cdr w) (+ m (car w)) p)
          (sum (cdr w) m (+ p (car w))))
      (values m p)))
 
> (sum-m-p '(-3 -2 -1 0 1 2 3))
-6
6

(defun sum-m-p (w) (sum w 0 0))
 
(defun sum (w m p &aux (a (car w)))
  (if w
      (if (minusp a)
          (sum (cdr w) (+ m a) p)
          (sum (cdr w) m (+ p a)))
      (values m p)))
 
> (sum-m-p '(-3 -2 -1 0 1 2 3))
-6
6

(defun sum-m-p (w) (sum w 0 0))
 
(defun sum (w m p &aux (a (car w)))
  (if w (let ((z (minusp a)))
          (sum (cdr w) (if z (+ m a) m) (if z p (+ p a))))
      (values m p)))
 
> (sum-m-p '(-3 -2 -1 0 1 2 3))
-6
6

(defun sum-mp (w)
  (list (sm w #'minusp) (sm w #'plusp)))
 
(defun sm (w f &optional (n 0) &aux (a (car w)))
  (if w (sm (cdr w) f (if (funcall f a) (+ n a) n)) n))
 
> (sum-mp '(-3 -2 -1 0 1 2 3))
(-6 6)

(defun sum-mp (w)
  (values (sm w #'minusp) (sm w #'plusp)))
 
(defun sm (w f &optional (n 0) &aux (a (car w)))
  (if w (sm (cdr w) f (if (funcall f a) (+ n a) n)) n))
 
> (sum-mp '(-3 -2 -1 0 1 2 3))
-6
6

(defun sum-mp (w)
  (values (sm w #'minusp) (sm w #'plusp)))
 
(defun sm (w f)
  (loop for a in w when (funcall f a) sum a))
 
> (sum-mp '(-3 -2 -1 0 1 2 3))
-6
6

(defun summp (w)
  (values (reduce #'+ (remove-if #'plusp w)) 
          (reduce #'+ (remove-if #'minusp w))))
 
> (summp '(-3 -2 -1 0 1 2 3))
-6
6

(defun summmp (w)
  (values (sm w #'minusp) (sm w #'plusp)))
 
(defun sm (w f)
  (reduce #'+ (remove-if f w)))
 
> (summmp '(-3 -2 -1 0 1 2 3))
6
-6

(defun task (lst)
  (cond ((null lst) (list 0 0))
        (t (let ((ss (task (cdr lst))))
              (if (plusp (car lst)) (list (+ (car lst) (car ss)) (cadr ss))
                                    (list (car ss) (+ (car lst) (cadr ss))))))))
 
==> TASK
 
(task '(1 2 -5 -6 0 0))
 
==> (3 -11)

(defun summmp (w)
  (values (sm w #'minusp) (sm w #'plusp)))
 
(defun sm (w f)
  (eval (cons '+ (loop for a in w unless (funcall f a) collect a))))
 
> (summmp '(-3 -2 -1 0 1 2 3))
6
-6

(defun summmp (w)
  (labels ((sum (v m p) 
             (cond ((null v) (list m p))
                   ((minusp (car v)) (sum (cdr v) (+ m (car v)) p))
                   (t (sum (cdr v) m (+ p (car v)))))))
    (sum w 0 0)))
 
> (summmp '(-3 -2 -1 0 1 2 3))
(-6 6)

(defun summmp (w)
  (labels ((sum (v m p &aux (a (car v))) 
             (cond ((null v) (list m p))
                   ((minusp a) (sum (cdr v) (+ m a) p))
                   (t (sum (cdr v) m (+ p a))))))
    (sum w 0 0)))
 
> (summmp '(-3 -2 -1 0 1 2 3))
(-6 6)