main :: IO()
main = getContents >>= print.(\[x, y, l] -> g x l + g y l + solve x y).map read.lines
    where g x l = ceiling $ (fromIntegral.abs) x / fromIntegral l
         
solve :: Int -> Int -> Int
solve 0 y | y >= 0    = 0
solve x y | y >= 0    = 1
          | otherwise = 2