(defun main (&rest argv)
  (declare (ignorable argv))
  (let* ((g (read))
         (c (read))
         (p (read))
         (s (read-line))
         (gg (count #\G s))
         (cc (count #\C s))
         (pp (count #\P s))
         (res 0))
    (incf res (* 3 (+ (min g cc) (min c pp) (min p gg))))
    (setf g  (- g (min g cc))
          cc (- cc (min g cc)))
    (setf c  (- c (min c pp))
          pp (- pp (min c pp)))
    (setf p  (- p (min p gg))
          gg (- gg (min p gg)))
    (incf res (+ (min g gg) (min c cc) (min p pp)))
    (format t "~d~%" res)))

(main)