f x = do
    let hour = div x 3600
    let minute = div (x - hour * 3600) 60
    let sec = x - hour * 3600 - minute * 60
    (show hour) ++ ":" ++ (show minute) ++ ":" ++ (show sec)

main = do
    x <- readLn ::IO Int
    putStrLn $f x
