Eight white chess knights are placed on a 3x4 chessboard, four along the top row and four along the bottom, which are labeled as P, Q, R, S, T, U, V and W, as shown in the figure.
Exchange the positions of P and T, Q and U, R and V, and S and W in minimum possible number of moves.
Let the squares be identified from 1 through 12 being read from left to right down.
(In reply to
One possible solution by Dej Mar)
Firstly:
I copied the move set offered by Dej Mar to ascertain the number of moves made by each piece:
P Q R S T U V W
4 6 6 4 2 4 4 2
Secondly:
I notice that Q revisits the same cell twice in sets 7 and 17 and R similarly revisits a cell twice in sets 19 and 25. Does that mean that there is still a more efficient way to exchange the pieces, or is that something that has too happen?
Edited on February 17, 2010, 7:20 pm

Posted by brianjn
on 20100216 21:08:19 