Status

ChessProblem

The problem is to find all unique configurations of a set of normal chess pieces on a chess board with dimensions M×N where none of the pieces is in a position to take any of the others. The colour of the piece does not matter, and that there are no pawns among the pieces.

How to run program for 7×7 board with 2 Kings, 2 Queens, 2 Bishops and 1 Knight

1. In Intellij IDEA run Worksheet.sc
2. In the console using sbt

$ export SBT_OPTS="-Xmx4G -XX:+UseConcMarkSweepGC -XX:+CMSClassUnloadingEnabled -XX:MaxPermSize=4G -Xss2M"
$ sbt console
[info] Set current project to chess-problem (in build file:/Users/vm/development/sworkspace/ChessProblem/)
[info] Starting scala interpreter...
[info] 
Welcome to Scala version 2.11.2 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_25).
Type in expressions to have them evaluated.
Type :help for more information.

scala> import com.kgrodzicki.chessproblem._
import com.kgrodzicki.chessproblem._

scala> val game = new App(7, 7, List(King, King, Queen, Queen, Bishop, Bishop, Knight))
game: com.kgrodzicki.chessproblem.App = com.kgrodzicki.chessproblem.App@3bd2057d

scala> game.show()
3063828 solutions for King=2, Queen=2, Bishop=2, Knight=1 on board 7*7
. . . . B . . 
. . Q . . . . 
. . . . K . . 
. . . . . . Q 
. . . B . . . 
. K . N . . . 
. . . . . . . 

Q . . . . . . 
. . . B N . B 
. . . . . . . 
. . . . . . K 
. . . . . . . 
. Q . . . . . 
. . . . K . . 

Q . . . . . . 
. . . B N . K 
. . . . . . . 
. . . . . . K 
. . . . . . . 
. Q . . . . . 
. . . . B . . 

. . . . . . . 
. . . . . . Q 
. B . . . . . 
. N . . . K . 
. . . . . . . 
. . . K . B . 
Q . . . . . . 

. . . Q . . . 
. . . . . . N 
Q . . . . . . 
. . . . . . . 
. . . . K . B 
. . . . . . . 
. . K . . B . 

. . . Q . . . 
. . . . . . B 
Q . . . . . . 
. . . . . . . 
. . . . K . K 
. . . . . . . 
. . N . . B . 

. . . Q . . . 
. . . . . . K 
Q . . . . . . 
. . . . . . . 
. . . . K . B 
. . . . . . . 
. . N . . B . 

. . . Q . . . 
. . . . . . B 
Q . . . . . . 
. . . . . . . 
. . . . K . B 
. . . . . . . 
. . N . . K . 

. B . . . K . 
. . . Q . . . 
. . . . . . . 
. . . . . . Q 
. . . . . . . 
K . . . . . . 
. . B . N . . 

. K . . . . N 
. . . . . . B 
Q . . . . . . 
. . . . . Q . 
. . . . . . . 
. K . . . . . 
. . . . . . B 


scala> :q

[success] Total time: 196 s, completed Aug 1, 2014 11:46:07 AM

where:

• K -> King
• Q -> Queen
• B -> Bishop
• N -> Knight

Program lists 10 unique configurations to the console