Day 3: Mull It Over

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FAQ

  • janAkaliEnglish
    5•10 days ago

    Nim

    From a first glance it was obviously a regex problem.
    I’m using tinyre here instead of stdlib re library just because I’m more familiar with it.

    import pkg/tinyre

proc solve(input: string): AOCSolution[int, int] =
  var allow = true
  for match in input.match(reG"mul\(\d+,\d+\)|do\(\)|don't\(\)"):
    if match == "do()": allow = true
    elif match == "don't()": allow = false
    else:
      let pair = match[4..^2].split(',')
      let mult = pair[0].parseInt * pair[1].parseInt
      result.part1 += mult
      if allow: result.part2 += mult

    Codeberg repo

    • @sjmulder
      5•10 days ago

      I shy away from regexes for these parsing problems because part 2 likes to mess those up but here it worked beautifully. Nice and compact solution!