free samples

gistfile1.clj

(defn eat-well [vendors]
  (loop [[[item & others] newest older oldest] [vendors 0 0 0]]
    (if item
      (recur [others (+ item (max older oldest)) newest older])
      (max newest older oldest))))

(eat-well [1 4 3 12 4 3 3 4])

Alex's formulation is equivalent but slightly nicer; it just does the max one step earlier.

(defn eat-well [vendors]
  (loop [[[item & others] exclude include] [vendors 0 0]]
    (if item
      (recur [others (+ item include) (max include exclude)])
      (max include exclude))))