(defn arg-max
([func lst] (arg-max func lst (first lst)))
([func lst best]
(cond
(= best nil) nil
(= (first lst) nil) best
(< (func best) (func (first lst))) (recur func (rest lst) (first lst))
:else (recur func (rest lst) best)
)
)
)
(println (arg-max (fn [x] (* x x)) '(1 -3 2 -5 4)))