(import
  (scheme base)
  (scheme read)
  (scheme write)
)


(define yuki9011
  (let*
    ((n (read)))
    (let loop
      (
        (i n)
        (s 0)
      )
      (if (zero? i)
        (begin (display s) (newline))
        (loop (quotient i 10) (+ s (modulo i 10)))
      )
    )
  )
)