In a coordinate system four gaming pieces are placed (only full coordinates are allowed like (0|1), not like (1/3|5.2)).
When these pieces are moved, the following conditions must be fulfilled: one piece (K) can only be moved if there is another piece (L) in the middle of his (K) old and his (K) new position.
At the beginning the four pieces are placed at (0|0), (0|1), (1|0) and (1|1). Is it possible that at some stage the pieces are located (0|0), (1|1), (3|0)and (2|-1).
Is this possible?
I've tried it but either it is not possible or it's just too advanced logic stuff for me....