code: public static int ceiling(int n, int m) {
          return n >= 0 ? ((n + m - 1) / m) * m : (n / m) * m;
      }
docs: Rounds n up to the nearest multiple of m
  
  @param n an integer
  @param m an integer
  @return the value after rounding {@code n} up to the nearest multiple of {@code m}