The diagram shows a restricted chess board with three black knights and three white knights. Your goal is to move the pieces so that the same squares are occupied but the colors are reversed. Your first move must use a black piece.
Pieces may move only as a normal chess knight, from one corner of a 2×3 rectangle to the opposite corner. No more than one piece may occupy a single square at a time. No piece may move onto a darkened square. No other rules of chess apply.
One turn is a sequence of moves made by a single piece. Find a solution with the minimum number of turns.
One of several computer solutions that are being devoloped is:
A4B2
E2C3
C3A4
B1C3
D2B1
C3E2
D5C3
E2D4
B1D2
B4D5
C3B1
D5C3
C3E2
B1C3
C3D5
D5B4
E2C3
D2B1
C3D5
B1C3
C3E2
D5C3
C3B1
B1D2
A4C3
B2A4
C3B1
A4C3
C3D5
E2C3
C3A4
D4E2
This has 32 moves. If I've counted right, there are 9 instances where the sending square on a given move is the same as the receiving square on the previous (indicating a continued move by the same knight), making it 23 turns.
Edited on December 10, 2004, 9:22 pm

Posted by Charlie
on 20041210 21:19:39 