#| BEGIN (Введите свое решение) |#
(define (successive-merge set)
  (if (= (length set) 1)
      (car set)
      (let* ((first (car set))
             (second (cadr set))
             (rest (cddr set))
             (combined (make-code-tree first second)))
        (successive-merge (adjoin-set combined rest)))))
#| END |#