Max Slice Sum

Lisp Max Slice Sum

(defun max-slice-sum (a)
  (let ((tmp most-negative-fixnum)
        (max most-negative-fixnum))
    (dolist (v a)
      (setf tmp (max (+ tmp v) v))
      (setf max (max max tmp)))
    max))

This is a Kadane-style scan: keep the best running sum and the best overall sum while moving once through the array.