Task: Mirror trap

A mirror trap is a cuboid made of mirrors, the reflecting sides of which are facing the interior of the cuboid. Precisely in the geometric centre of the cuboid there is a miniature laser (whose dimensions we shall neglect). The task is to aim the laser in such a way that the beam travels the longest total distance possible and returns to the laser itself. By total distance we shall denote the sum of distances traveled by the laser beam in each of the three directions parallel to the edges of the mirrors (i.e. we are using the so called Manhattan (city) metric).

The dimensions of the trap are even integers. The edges and vertices of the trap, where distinct sides meet, do not reflect the laser beam. Inside the cuboid we shall introduce a cartesian coordinate system. Its axes are parallel to the edges of the trap and the laser shall be placed in the origin. The laser may be aimed at any integer point (a point whose all coordinates are integers) within the trap, the points on the surface of the mirrors included (with the single exception of the laser itself, i.e. the point (0, 0, 0)).

Task

• reads from the standard input the dimensions of the mirror trap,
• calculates such a point, that a laser beam fired from the laser it the direction of this point:
  • shall be reflected from the mirrors (but not necessarly from all of them),
  • shall neither intersect an edge nor a vertex of the mirror trap,
  • shall return to the laser, possibly from a different direction,
  • shall travel the longest total distance possible (in the sense of the definition provided).
• writes the outcome to the standard output.

Input

Output

Should there be a greater number of correct solutions, your programme ought to write out any one of them.

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