AoC 2025, day 25 (smalltalk)

#!/usr/local/bin/gst -q

Symbol extend [ value: arg [^arg perform: self] ]

" Changes to booleans to give basic integer coercion: "
Boolean extend  [ generality [^1] ]
True  extend    [ truncated  [^1] ]
False extend    [ truncated  [^0] ]

"
|  Mainline
"
locks := Set new.
keys  := Set new.

((stdin contents tokenize: '\n\n') collect: #lines) do: [:item |
    " Convert images to bitArrays, AND them and any overlap will be a 1: "
    bitArray := item join inject: 0 into: [:a :b | a * 2 + (b = $#)].

    ((item first first = $#) ifTrue: [locks] ifFalse: [keys]) add: bitArray.
].

part1 := locks inject: 0 into: [:sum :l | sum + (keys count: [:k | (k bitAnd: l) = 0])].
('Part 1: %1' % {part1}) displayNl.