Paste: AOC day 3

USING: io.encodings.ascii io.files kernel literals math
math.matrices math.parser math.statistics prettyprint sequences ;

CONSTANT: input $[ "input.txt" ascii file-lines ]

: 1|0 ( ? -- n ) CHAR: 1 CHAR: 0 ? ;

: part1 ( -- )
    input flip [ mode ] map dup [ CHAR: 0 = 1|0 ] map
    [ bin> ] bi@ * . ;

: s ( seq n -- count ) [ = ] curry count ;
: counts ( seq -- 1s 0s ) [ CHAR: 1 s ] [ CHAR: 0 s ] bi ;
: oxygen ( seq -- n ) counts >= 1|0 ; ! a custom mode
: co2 ( seq -- n ) counts < 1|0 ;     ! a custom mode

! Filter sequence of binary numbers by bit criteria of the nth
! bit given a mode quotation.
: pare ( ... n seq quot: ( ... seq -- ... mode ) -- ... newseq )
    [ 2dup col ] dip call swapd '[ _ swap nth _ = ] filter ;
    inline

! Find the rating given a mode quotation.
: rating ( ... seq quot: ( ... seq -- ... mode ) -- ... n )
    0 -rot [ [ dup length 1 > ] ] dip
    '[ dupd _ pare [ 1 + ] dip ] while nip first bin> ; inline

: part2 ( -- )
    input [ oxygen ] rating input [ co2 ] rating * . ;

part1 part2