You and an opponent are seated at a table, and on the table is a square board. At each of the four corners of the board, there is a disc, each one red on one side and black on the other. You are blindfolded, and thus cannot see the configuration of the discs, but you claim that you can flip the discs such that they are all facing with the same color up. On each move, you can flip either one or two discs (either adjacent or diagonal to each other). If this results in a winning state, your opponent must announce that. Otherwise, your opponent may choose to rotate the board 0°, 90°, 180°, or 270°. Find the shortest sequence of moves that is guaranteed to win the game, no matter what rotations of the board are made. Be sure to include a proof that your solution is correct and that it is the shortest possible.