Paste: AOC day 20 part 1

USING: accessors assocs columns io.encodings.ascii io.files
kernel literals math.parser prettyprint sequences
sequences.extras sets sets.extras splitting strings ;
IN: aoc.2020.20

<<

: ?>string ( obj -- obj/str ) dup sequence? [ >string ] when ;

: prune ( seq -- first last )
    [ first ] [ last ] bi [ ?>string ] bi@ ;

: (edges) ( seq -- newseq )
    [ [ prune ] [ <flipped> prune ] bi ] [ 4sequence ] bi ;

: edge>id ( seq -- n )
    { { CHAR: . CHAR: 0 } { CHAR: # CHAR: 1 } }
    substitute bin> ;

: edges ( seq -- newseq )
    (edges) dup [ reverse ] map append [ edge>id ] map ;

TUPLE: tile data id edges ;
C: <tile> tile

>>

CONSTANT: input $[
    "input2.txt" ascii file-lines { "" } split
    [ unclip "Tile: " without dec> over edges <tile> ] map
]

: part1 ( -- )
    input [ edges>> ] map-concat non-repeating input
    [ edges>> intersect length 4 = ] with filter
    [ id>> ] map-product . ;