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sudoku: some cleanup.

db4
John Benediktsson 2014-06-10 15:46:54 -07:00
parent 64aa894fee
commit 522bc270cc
1 changed files with 17 additions and 29 deletions
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46
extra/sudoku/sudoku.factor
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@ -1,6 +1,6 @@
! Based on http://www.ffconsultancy.com/ocaml/sudoku/index.html
USING: sequences namespaces kernel math math.parser io
io.styles combinators columns ;
USING: columns combinators combinators.short-circuit io
io.styles kernel math math.parser namespaces sequences ;
IN: sudoku
SYMBOL: solutions
@ -11,48 +11,36 @@ SYMBOL: board
: row ( n -- row ) board get nth ;
: board> ( m n -- x ) row nth ;
: >board ( row m n -- ) row set-nth ;
: f>board ( m n -- ) f -rot >board ;
: row-any? ( n y -- ? ) row member? ;
: col-any? ( n x -- ? ) board get swap <column> member? ;
: cell-any? ( n x y i -- ? ) 3 /mod pair+ board> = ;
: box-any? ( n x y -- ? )
[ 3 /i 3 * ] bi@
9 iota [ [ 3dup ] dip cell-any? ] any?
[ 3drop ] dip ;
[ 3 /i 3 * ] bi@ 9 iota [ cell-any? ] with with with any? ;
: board-any? ( n x y -- ? )
{ [ nip row-any? ] [ drop col-any? ] [ box-any? ] } 3|| ;
DEFER: search
: assume ( n x y -- )
[ >board ] 2keep [ [ 1 + ] dip search ] 2keep f>board ;
[ >board ] [ [ 1 + ] dip search f ] [ >board ] 2tri ;
: attempt ( n x y -- )
{
{ [ 3dup nip row-any? ] [ 3drop ] }
{ [ 2over col-any? ] [ 3drop ] }
{ [ 3dup box-any? ] [ 3drop ] }
[ assume ]
} cond ;
3dup board-any? [ 3drop ] [ assume ] if ;
: solve ( x y -- ) 9 [ 1 + 2over attempt ] each-integer 2drop ;
: solve ( x y -- )
9 [ 1 + 2over attempt ] each-integer 2drop ;
: cell. ( cell -- )
[ [ number>string write ] [ "." write ] if* ] with-cell ;
: row. ( row -- )
[ [ cell. ] each ] with-row ;
: board. ( board -- )
standard-table-style [
[
[
[
[
[
number>string write
] [
"." write
] if*
] with-cell
] each
] with-row
] each
] tabular-output nl ;
standard-table-style [ [ row. ] each ] tabular-output nl ;
: solution. ( -- )
solutions inc "Solution:" print board get board. ;