Advent of Code 2020 Day14

aoc202014.dyalog

DAY14←{('10X'=⊂7↓0⊃⍵)({⍎⍕'\d+'⎕S'&'⊢⍵}¨1↓⍵)}¨({'mask'≡4↑⍵}¨d)⊂d←⊃⎕NGET'data/2020/day14.txt'1
mem←65435/0
_←{(0⊃⍵)∘{mem[0⊃⍵]←2⊥(((36⍴2)⊤1⊃⍵)∨0⊃⍺)∧~1⊃⍺⋄⍬}¨1⊃⍵}¨DAY14
+/mem ⍝ Part 1

mem←⍬  ⍝ Need the whole 36-bit address space, but sparsely populated
val←⍬
SetMem←{i←mem⍳⍵⋄i<≢mem:⍬⊣val[i]←⍺⋄mem,←⍵ ⋄ val,←⍺⋄⍬}
Addr←{
    b←((36⍴2)⊤0⊃⍵)∨0⊃⍺            ⍝ Address in binary, with set-bit mask applied
    bits←{⍉(⍵⍴2)⊤⍳2*⍵} +/flb←2⊃⍺
    all←(≢bits)(≢b)⍴b
    all[;⍸flb]←bits               ⍝ 'all' now contains all expanded floating bits
    _←(1⊃⍵)∘SetMem¨2⊥¨↓all
    ⍬
}

_←{(0⊃⍵)∘Addr¨1⊃⍵}¨DAY14
+/val ⍝ Part 2