Say pieces on a board, make each piece a pair with another piece. like...
|55|33|66| |44|66|55| |33|44|22| |22|11|11| a piece can only be figured out to move one way... pick any piece, try to move it somewhere... have the chosen piece move to another piece, it moves there and makes the other piece have to move too. when a piece is moved to another piece, it becomes a pair with the piece it moves to. any piece that is moved has to have it's pair move at the same time. any piece to move to another piece is a piece that moved at the same time as it's pair, and moved to another piece that moved at the same time as it's pair too. A piece that moves to another piece becomes a pair with it, and the other of the pair has moved to become a pair with another piece. try anyway, works in one way where a piece can move back to the piece to move first. A common type of problem, I forget what it's called. A piece always goes where a piece leaves, the first piece has the last piece go where it left. You can't move a piece that moves where the piece came from. There is no such thing as a free space, a piece always moves to another piece. A pair never moves to a pair. A piece works out to move where another piece can get back to where a piece moves from. The last move has to be known for the first move to be made, because the first move can't be understood until the last move is. That's because the first move is where a piece moves to and it works around to the last move, and the last move is where a piece can work getting to from the first move. so try this... draw starting at each piece a line that shows the piece it moves to, and each piece to move for how a piece moves back where it starts. see this as a machine diagram. move a piece then figure the machine diagram again, it's the same machine though... see how every other piece moves another way now? what happened for how the machine moved? _how did the machine move though_ ????
