Paste: My attempt at AOC part 12 (half a year later)

! day 12
! from day 4 solution:
! : iterate-through-everything ( ... grid quot: ( ... x y grid -- ... ) -- ... ) over first length [ -rot over length [ -roll call ] 3with each-integer ] 2with each-integer  ; inline
! : at-coord ( x y grid -- val ) swapd nth nth ;
! from day 8 solution:
! : by-cols ( grid -- cols ) [ first length ] keep [ [ nth ] with map ] curry map-integers ;

: adjecent-to-one? ( x1 y1 x2 y2 -- ? ) swapd [ - abs ] 2bi@ + >float 1.0 = ;
: adjecent-to? ( others x y -- ? ) [ [ first2 ] 2dip adjecent-to-one? ] 2curry find nip ;
: any-adjecent-to? ( regions region -- ? ) [ first2 adjecent-to? ] cartesian-find drop ;
: count-adjecent ( others x y -- n ) [ [ first2 ] 2dip adjecent-to-one? ] 2curry filter length ;
: excluding ( seq n -- seq ) [ head ] [ 1 + tail ] 2bi append ;
: pop-start ( seq -- elt ) [ first ] [ 0 swap remove-nth! drop ] bi ;
: regions-from-coords ( coords -- regions ) 
    >vector [ 1vector ] map 
    0 
    [ 
        over length
        [ 
            dup pop-start 
            2dup any-adjecent-to? 
            [ swap append! drop t ] [ suffix! f ] if*
        ] 
        [ swap [ drop 0 ] [ 1 + ] if ]
        [ dupd < ] tri*
    ] loop drop ;
: generate-sides ( others x y -- sides ) 
    [ 
        {
            [ [ [ 1 + ] dip 2array swap index not ] 2keep rot [ [ 0.1 + ] dip 2array ] [ 2drop f ] if ]
            [ [ [ 1 - ] dip 2array swap index not ] 2keep rot [ [ 0.1 - ] dip 2array ] [ 2drop f ] if ]
            [ [ 1 + 2array swap index not ] 2keep rot [ 0.1 + 2array ] [ 2drop f ] if ]
            [ [ 1 - 2array swap index not ] 2keep rot [ 0.1 - 2array ] [ 2drop f ] if ]
        } 3cleave
    ] output>array sift ;
: generate-side-regions ( region -- side-regions ) 
    dup V{ } clone [ first2 generate-sides append! ] with reduce regions-from-coords ;
: region-number ( region -- number ) [ length ] keep dup 0 [ first2 count-adjecent 4 swap - + ] with reduce * ;
: pt2-region-number ( region -- number ) [ length ] keep generate-side-regions length * ;
: grid-to-regions ( grid -- regions ) 
    H{ } clone 
    [ 
        [ 
            [ 
                [ at-coord ] 2keepd 2array swap 
            ] dip
            push-at 
        ] curry iterate-through-everything 
    ] keep
    V{ } clone [ nip regions-from-coords append! ] assoc-reduce >array
    ;
: grid-to-solution ( grid -- number ) grid-to-regions [ region-number ] map sum ;
: grid-to-pt2-solution ( grid -- number ) grid-to-regions [ pt2-region-number ] map sum ;
: parse-day-twelve-input ( string -- grid ) split-lines harvest by-cols ;
: solve-day-twelve ( string -- number ) parse-day-twelve-input grid-to-solution ;
: solve-day-twelve-part-two ( string -- number ) parse-day-twelve-input grid-to-pt2-solution ;
Author:	Leo Mehraban
Mode:	factor
Date:	Thu, 14 Aug 2025 12:19:19