module Main where

import Control.Applicative
import Numeric
import Data.Char

main :: IO ()
main = loop

loop :: IO ()
loop = do
  { [n] <- getIntegers
  ; if n == 0 then return ()
    else do
      {print (sum(map digitToInt (show n)))
      ; loop
      }
  }
  
--
getIntegers :: IO [Integer]
getIntegers = map read . words <$> getLine

getInts :: IO [Int]
getInts = map read . words <$> getLine

putInts :: [Int] -> IO ()
putInts = putStrLn . unwords .  map show

getDoubles :: IO [Double]
getDoubles = map read . words <$> getLine

putDoubles :: [Double] -> IO ()
putDoubles = putStrLn . unwords . map showDouble

showDouble :: Double -> String
showDouble d = showFFloat Nothing d ""
