Day 3: Mull It Over
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1 point
Smalltalk
I wrote matchesActual cause all of smalltalk’sstupid matchesDo: or whatever don’t give you the actual match with captures, only substrings (that wasted a good 40 minutes).
Also smalltalk really needs an index operator
day3p1: input
| reg sum |
reg := 'mul\((\d\d?\d?),(\d\d?\d?)\)' asRegex.
sum := 0.
reg matchesActual: input do: [ :m | " + sum at end cause operator precedence"
sum := (m subexpression: 2) asInteger * (m subexpression: 3) asInteger + sum
].
^ sum.
day3p2: input
| reg sum do val |
reg := 'do(\:?n''t)?\(\)|mul\((\d{1,3}),(\d{1,3})\)' asRegex.
sum := 0.
do := true.
reg matchesActual: input do: [ :m |
val := m subexpression: 1.
(val at: 1) = $d ifTrue: [ do := (val size < 5) ]
ifFalse: [
do ifTrue: [
sum := (m subexpression: 2) asInteger * (m subexpression: 3) asInteger + sum.
]. ].
].
^ sum.
