Fly in the cube

The game field is a cube (3D variant) or - a square (2D variant). In the playing field is the object of the game - the fly. The initial position of the "fly" is the central cell of the playing field (in 3D version - the fly is turned with its back to the player). When a player makes a move, he moves the fly one cell on any of the dimensions of the game space (left-right, forward-backward, down-up). The player's task is not to let the fly out of the playing field.