import Data.Char

main = do
  [a,b,s] <- words <$> getLine
  let m = read a * 60 + read b
  let sig = if any (=='+') s then 1 else (-1)
  let d = sig * (read $ takeWhile isDigit $ dropWhile (not.isDigit) s) - 9
  let f = if any (=='.') s then True else False
  let m' = mod (m + d * 60 + if f then 30 else 0 + 1440) 1440
  putStrLn $ show2 (div m' 60) ++ ":" ++ show2 (mod m' 60)

show2 = reverse . take 2 . reverse . ("0" ++) . show