(defn inter [ls1 ls2]
  (let [length1 (count ls1)
        length2 (count ls2)]
    (if (zero? (min length1 length2))
      '()
      (list
        (first ls1)
        (first ls2)
        (inter (rest ls1) (rest ls2))))))

(println (inter '(1 2 3) '("foo" "bar" "baz")))