(defun solve ()
    (let ((s (read-line)) (i 0) (answer 0))
    (loop while (< i (length s)) do
        (if (digit-char-p (char s i))
            (setf answer (+ answer (- (char-code (char s i)) (char-code #\0)))))
        (incf i))
    answer))

(defun main () (format t "~A~%" (solve)))

(main)