this post was submitted on 07 Dec 2023
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Advent Of Code

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Advent of Code is an annual Advent calendar of small programming puzzles for a variety of skill sets and skill levels that can be solved in any programming language you like.

AoC 2024

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Day 7: Camel Cards

Megathread guidelines

  • Keep top level comments as only solutions, if you want to say something other than a solution put it in a new post. (replies to comments can be whatever)
  • Code block support is not fully rolled out yet but likely will be in the middle of the event. Try to share solutions as both code blocks and using something such as https://topaz.github.io/paste/ , pastebin, or github (code blocks to future proof it for when 0.19 comes out and since code blocks currently function in some apps and some instances as well if they are running a 0.19 beta)

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[–] [email protected] 6 points 1 year ago* (last edited 1 year ago) (1 children)

Nim

I wrote some nice code for sorting poker hands, just defining the < and == operations for my CardSet and Hand types, and letting the standard library's sort function handle the rest.

It was quite frustrating to be told that my answer was wrong, though. I dumped the full sorted hand list and checked it manually to make sure everything was working properly, and it was. Wasted a few hours trying to figure out what was wrong. Ended up grabbing someone else's code and running it in order to compare the resulting hand list. Theirs was clearly ordered wrong, but somehow ended up with the correct answer?

Turns out that Camel Cards isn't Poker. -_-

Rather than rewrite my code entirely, I settled on some slightly ugly hacks to make it work for Camel Cards, and to handle the wildcards in part 2.

[–] [email protected] 1 points 1 year ago

Hi there! Looks like you linked to a Lemmy community using a URL instead of its name, which doesn't work well for people on different instances. Try fixing it like this: [email protected]

[–] mykl 4 points 1 year ago* (last edited 1 year ago) (2 children)

It's Uiua time!

It works, but even I can't understand this code any more as I'm well into my second beer, so don't put this into production, okay? (Run it here if you dare.)

{"32T3K 765"
 "T55J5 684"
 "KK677 28"
 "KTJJT 220"
 "QQQJA 483"}
StoInt ← /(+Γ—10)β–½Γ—βŠƒ(β‰₯0)(≀9).-@0
ToHex ← ⊏:"  23456789abcde"βŠ—:"  23456789TJQKA"
ToHexJ ← ⊏:"  23456789a0cde"βŠ—:"  23456789TJQKA"
# A hand of "311" with one J will have same rank as "41"
# Dots indicate impossible hands.
Rankings ← {
  {"11111" "2111" "221" "311" "32" "41" "5"}   # 0
  {"..." "11111" ".." "2111" "221" "311" "41"} # 1
  {"..." "....." ".." "2111" "..." "221" "32"} # 2
  {"..." "....." ".." "...." "..." "311" "32"} # 3
  {"..." "....." ".." "...." "..." "..." "41"} # 4
  {"..." "....." ".." "...." "..." "..." "5"}  # 5
}
RankHand ← (
  +@0βŠβ–.βŠ•β§»βŠ›βŠ’β‰β‡ŒβŠ•βˆ˜β–...          # Count instances, sort desc, to string
  βŠ—βŠƒβŠ’(βŠ”βŠ‘:Rankings/+=@0βŠ’β†˜1)βŠŸβˆ©β–‘ # Use table to get ranking
)
ScoreHands! ← (
  ≑(βŠβŠŸβŠ“(⊐⊟RankHand.^1βŠ”)∘⍘⊟) # Rank every hand
  /+/Γ—βŠŸ+1⇑⧻.βˆ΅βŠ”β‰‘(βŠ’β†˜1)βŠββ‰‘βŠ’.   # Sort based on rankings
)
β‰βŠŸβŠ“βˆ˜(∡StoInt)β˜βŠŸβ‰β‰‘(βŠβŠœβˆ˜β‰ @\s.) # Parse input
βŠƒ(ScoreHands!ToHex)(ScoreHands!ToHexJ)

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago) (1 children)

How do you debug this language??

[–] mykl 1 points 1 year ago

Lots and lots of print statements :-)

[–] [email protected] 2 points 1 year ago

Lord have mercy upon our souls

[–] mykl 4 points 1 year ago* (last edited 1 year ago)

Dart

I'm glad I took the time to read the directions very carefully before starting coding :-)

Top Tip: my ranking of hand types relies on the fact that if you count instances of each face and sort the resulting list from high to low, you get a list that when compared with lists from other hands gives an exact correspondence with the order of the hand types as defined, so no need for a bunch of if/thens, just

  var type = Multiset.from(hand).counts.sorted(descending).join('');

Otherwise it should all be pretty self-explanatory apart from where I chose to map card rank to hex digits in order to facilitate sorting, so 'b' means 'J'!

int descending(T a, T b) => b.compareTo(a);
var cToH = "  23456789TJQKA"; // used to map card rank to hex for sorting.

handType(List hand, {wildcard = false}) {
  var type = Multiset.from(hand).counts.sorted(descending).join('');
  var i = hand.indexOf('b');
  return (!wildcard || i == -1)
      ? type
      : '23456789acde'
          .split('')
          .map((e) => handType(hand.toList()..[i] = e, wildcard: true))
          .fold(type, (s, t) => s.compareTo(t) >= 0 ? s : t);
}

solve(List lines, {wildcard = false}) => lines
    .map((e) {
      var l = e.split(' ');
      var hand =
          l.first.split('').map((e) => cToH.indexOf(e).toRadixString(16));
      var type = handType(hand.toList(), wildcard: wildcard);
      if (wildcard) hand = hand.map((e) => e == 'b' ? '0' : e);
      return (hand.join(), type, int.parse(l.last));
    })
    .sorted((a, b) {
      var c = a.$2.compareTo(b.$2);
      return (c == 0) ? a.$1.compareTo(b.$1) : c;
    })
    .indexed(offset: 1)
    .map((e) => e.value.$3 * e.index)
    .sum;

part1(List lines) => solve(lines);

part2(List lines) => solve(lines, wildcard: true);
[–] [email protected] 3 points 1 year ago

Scala3

val tiers = List(List(1, 1, 1, 1, 1), List(1, 1, 1, 2), List(1, 2, 2), List(1, 1, 3), List(2, 3), List(1, 4), List(5))
val cards = List('2', '3', '4', '5', '6', '7', '8', '9', 'T', 'J', 'Q', 'K', 'A')

def cardValue(base: Long, a: List[Char], cards: List[Char]): Long =
    a.foldLeft(base)(cards.size * _ + cards.indexOf(_))

def hand(a: List[Char]): List[Int] =
    a.groupMapReduce(s => s)(_ => 1)(_ + _).values.toList.sorted

def power(a: List[Char]): Long =
  cardValue(tiers.indexOf(hand(a)), a, cards)

def power3(a: List[Char]): Long = 
  val x = hand(a.filter(_ != 'J'))
  val t = tiers.lastIndexWhere(x.zipAll(_, 0, 0).forall(_ <= _))
  cardValue(t, a, 'J'::cards)

def win(a: List[String], pow: List[Char] => Long) =
    a.flatMap{case s"$hand $bid" => Some((pow(hand.toList), bid.toLong)); case _ => None}
        .sorted.map(_._2).zipWithIndex.map(_ * _.+(1)).sum

def task1(a: List[String]): Long = win(a, power)
def task2(a: List[String]): Long = win(a, power3)
[–] [email protected] 3 points 1 year ago* (last edited 1 year ago)

Nim

Part 1 is just a sorting problem. Nim's standard library supports sorting with custom compare functions, so I only had to implement cmp() for my custom type and I was done in no time.
To get the star in Part 2 I was generating every possible combination of card hands with Jokers replaced by other cards. It was pretty fast, under a second. Didn't figure out the deterministic method by myself, but coded it after couple hints from Nim Discord people.
Didn't expect an easy challenge for today, but was pleasantly surprised. No weird edge cases, no hidden traps, puzzle text was easy to understand and input parsing is painless.

Total runtime: 1 ms
Puzzle rating: Almost Pefect 9/10
Code: day_07/solution.nim

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago)

Crystal

got stuck on both parts due to silly mistakes.
On the other hand I'm no longer behind!

code

input = File.read("input.txt").lines
rank = {
	'J' => 1,
	'2' => 2,
	'3' => 3,
	'4' => 4,
	'5' => 5,
	'6' => 6,
	'7' => 7,
	'8' => 8,	
	'9' => 9,
	'T' => 10,
	# 'J' => 11,
	'Q' => 12,
	'K' => 13,
	'A' => 14
}

hand = input.map do |line|
	split = line.split
	weights = split[0].chars.map {|c| rank[c]}
	{weights, split[1].to_i}
end

hand.sort! do |a, b|
	a_rank = get_rank(a[0], true)
	b_rank = get_rank(b[0], true)
	
	# puts "#{a}-#{a_rank} #{b}-#{b_rank}"
	next  1 if a_rank > b_rank
	next -1 if b_rank > a_rank

	val = 0
	5.times do |i| 
		val =  1 if a[0][i] > b[0][i]
		val = -1 if b[0][i] > a[0][i]
		break unless val == 0
	end
	val
end

sum = 0
hand.each_with_index do |card, i|
	sum += card[1]*(i+1)
end
puts sum


def get_rank(card : Array(Int32), joker = false ) : Float64 | Int32
	aa = card.uniq

	if joker
		card = aa.map { |c|
			combo = card.map {|a| a == 1 ? c : a }
			{combo, get_rank(combo)}
		}.max_by {|a| a[1]}[0]
		aa = card.uniq
	end
	
	rank = 6 - aa.size
	case rank
	when 3
		return 3.5 if card.count(aa[0]) == 3
		return 3   if card.count(aa[0]) == 2
		return 3   if card.count(aa[1]) == 2
		return 3.5
	when 4
		return 4 if card.count(aa[0]) == 3 || card.count(aa[0]) == 2
		return 4.5
	else 
		return rank
	end
end

[–] vole 2 points 1 year ago* (last edited 1 year ago)

Raku

My hand-type strength calculations could probably be trimmed down a bit. I didn't hit any big issues today.

View code on github

Code (note: doesn't currently display correctly on Lemmy website)

use v6;

sub MAIN($input) {
    my $file = open $input;

    grammar CamelCards {
        token TOP { +%"\n" "\n"*}
        token row {  " "  }
        token hand { \S+ }
        token bid { \d+ }
    }

    my $camel-cards = CamelCards.parse($file.slurp);
    my @rows = $camel-cards.map({ (..Str, ..Int) });
    my @ranked-rows1 = @rows.sort({hand-strength($_[0], &hand-type-strength1, '23456789TJQKA'.comb)});
    my $part-one-solution = (@ranked-rows1Β»[1] Z* 1..*).sum;
    say "part 1: $part-one-solution";

    my @ranked-rows2 = @rows.sort({hand-strength($_[0], &hand-type-strength2, 'J23456789TQKA'.comb)});
    my $part-two-solution = (@ranked-rows2Β»[1] Z* 1..*).sum;
    say "part 2: $part-two-solution";
}

sub hand-strength($hand, &hand-type-strength, @card-strengths) {
    my $strength = &hand-type-strength($hand);
    for $hand.comb -> $card {
        $strength = $strength +< 8 + @card-strengths.first({ $_ eq $card }, :k);
    }
    return $strength;
}

sub hand-type-strength1($hand) {
    my @sorted = $hand.comb.sort;
    my @runs = [1];
    my $card = @sorted[0];
    for @sorted[1..*] -> $new-card {
        if $new-card eq $card {
            @runs.tail += 1;
        } else {
            @runs.push(1);
            $card = $new-card;
        }
    }
    return do given @runs.sort {
        when .[0] == 5 { 6 } # Five of a kind
        when .[1] == 4 { 5 } # Four of a kind
        when .[1] == 3 { 4 } # Full House
        when .[2] == 3 { 3 } # Three of a kind
        when .[1] == 2 { 2 } # Two pair
        when .[3] == 2 { 1 } # One pair
        default { 0 } # High card
    };
}

sub hand-type-strength2($hand) {
    my @sorted = $hand.comb.grep(none /J/).sort;
    if @sorted.elems == 0 {
        return 6;
    } else {
        my @runs = [1];
        my $card = @sorted[0];
        for @sorted[1..*] -> $new-card {
            if $new-card eq $card {
                @runs.tail += 1;
            } else {
                @runs.push(1);
                $card = $new-card;
            }
        }
        @runs.=sort;
        @runs.tail += 5 - @sorted.elems;
        return do given @runs {
            when .[0] == 5 { 6 } # Five of a kind
            when .[1] == 4 { 5 } # Four of a kind
            when .[1] == 3 { 4 } # Full House
            when .[2] == 3 { 3 } # Three of a kind
            when .[1] == 2 { 2 } # Two pair
            when .[3] == 2 { 1 } # One pair
            default { 0 } # High card
        };
    }
}

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago)

Ruby

[email protected]

https://github.com/snowe2010/advent-of-code/blob/master/ruby_aoc/2023/day07/day07.rb

Gonna clean it up now, but pretty simple at the end of it all. Helps that ruby has several methods to make this dead simple, like tally, any?, all?, and zip


Cleaned up solution:

def get_score(tally)
  vals = tally.values
  map = {
    ->(x) { x.any?(5) } => 7,
    ->(x) { x.any?(4) } => 6,
    ->(x) { x.any?(3) && x.any?(2) } => 5,
    ->(x) { x.any?(3) && tally.all? { |_, v| v != 2 } } => 4,
    ->(x) { x.count(2) == 2 } => 3,
    ->(x) { x.one?(2) && tally.all? { |_, v| v <= 2 } } => 2,
    ->(x) { x.all?(1) } => 1,
  }
  map.find { |lambda, _| lambda.call(vals) }[1]
end

def get_ranking(lines, score_map, scores)
  lines.zip(scores).to_h.sort do |a, b|
    a_line, a_score = a
    b_line, b_score = b
    if a_score == b_score
      a_hand, _ = a_line.split
      b_hand, _ = b_line.split
      diff = a_hand.chars.zip(b_hand.chars).drop_while { |a, b| a == b }[0]
      card_1 = score_map.index(diff[0])
      card_2 = score_map.index(diff[1])
      card_1 <=> card_2
    else
      a_score <=> b_score
    end
  end
end

def calculate_total_winnings(ranking)
  max_rank = ranking.size
  (1..max_rank).sum(0) do |rank|
    line = ranking[rank - 1]
    _, bid = line[0].split
    bid.to_i * rank
  end
end

score_map_p1 = %w[. . 2 3 4 5 6 7 8 9 T J Q K A]
score_map_p2 = %w[. . J 2 3 4 5 6 7 8 9 T Q K A]

execute(1) do |lines|
  scores = lines.map do |line|
    hand, _ = line.split
    tally = hand.split('').tally
    get_score tally
  end
  ranking = get_ranking(lines, score_map_p1, scores)
  calculate_total_winnings ranking
end

execute(2) do |lines|
  scores = lines.map do |line|
    hand, _ = line.split
    hand_split = hand.split('')
    tally = hand_split.tally
    if hand_split.any? { |c| c == 'J' }
      highest_non_j = tally.reject { |k, v| k == 'J' }.max_by { |k, v| v }
      if highest_non_j.nil?
        tally = { 'A': 5 }
      else
        tally[highest_non_j[0]] += tally['J']
      end
      tally.delete('J')
    end
    get_score tally
  end
  ranking = get_ranking(lines, score_map_p2, scores)
  calculate_total_winnings(ranking)
end
[–] [email protected] 2 points 1 year ago

Rust

Getting the count of each card, the two highest counts easily show what type of hand we have. For part 2 I just added the number of jokers to the highest count.

I spent some time messing around with generics to minimize code duplication between the solutions to both parts. I could have absolutely just copied everything and made small changes, but now my solution is generic over puzzle parts.

[–] [email protected] 2 points 1 year ago

C#

Not too bad - I just scored every hand for the first part so I could easily sort it.

For the second part I just brute forced the replacements for the hand type matchinge (first digit of score)

Task1public class Day7Task1:IRunnable {

public static Dictionary CardValues = new Dictionary()
 {
     { '2', "01" },
     { '3', "02" },
     { '4', "03" },
     { '5', "04" },
     { '6', "05" },
     { '7', "06" },
     { '8', "07" },
     { '9', "08" },
     { 'T', "09" },
     { 'J', "10" },
     { 'Q', "11" },
     { 'K', "12" },
     { 'A', "13" }
 };
 
 public void Run()
 {
     //var inputLines = File.ReadAllLines("Days/Seven/Day7ExampleInput.txt");
     var inputLines = File.ReadAllLines("Days/Seven/Day7Input.txt");



     var hands = inputLines.Select(line =>
     {
         var split = line.Split(' ', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
         return new Hand(split[0],  split[1] );
     }).ToList();

     var sortedHands = hands.OrderBy(hand => hand.Score).ToList();

     long resultValue = 0;

     for (int i = 1; i < hands.Count()+1; i++)
     {
         resultValue += i * sortedHands[i-1].Bid;
     }

     Console.WriteLine("Result:" + resultValue);

 }

 public class Hand
 {
     public Hand(string cards, string bid)
     {
         Cards = cards;
         Bid = int.Parse(bid);
         Score = GenerateScore();
     }

     public string Cards { get; set; }
     public int Bid { get; set; }
     
     public long Score { get; }

     private long GenerateScore()
     {
         var resultString = new StringBuilder();
         var cardGroups = Cards.GroupBy(c => c).ToList();
         var groupCounts = cardGroups.OrderByDescending(g => g.Count()).Select(g => g.Count()).ToList();
         if (cardGroups.Count() == 1)
         {
             resultString.Append("7");
         }
         else if(cardGroups.Count() == 2 && (cardGroups[0].Count() == 4 || cardGroups[0].Count() == 1))
         {
             resultString.Append("6");
         }
         else if(cardGroups.Count() == 2 && (cardGroups[0].Count() == 3 || cardGroups[0].Count() == 2))
         {
             resultString.Append("5");
         }
         else if(cardGroups.Count() == 3 && (cardGroups[0].Count() == 3 || cardGroups[1].Count() == 3 || cardGroups[2].Count() == 3))
         {
             resultString.Append("4");
         }
         else if(cardGroups.Count() == 3 && groupCounts[0] == 2 && groupCounts[1] == 2 && groupCounts[2] == 1)
         {
             resultString.Append("3");
         }
         else if(cardGroups.Count() == 4 )
         {
             resultString.Append("2");
         }
         else
         {
             resultString.Append("1");
         }

         foreach (var card in Cards)
         {
             resultString.Append(Day7Task1.CardValues[card]);
         }

         Console.WriteLine("Cards:{0} Score:{1}",Cards,resultString);
         return long.Parse(resultString.ToString());
     }
 }
}

Task2

public class Day7Task2:IRunnable
{
    public static Dictionary CardValues = new Dictionary()
    {
        { '2', "01" },
        { '3', "02" },
        { '4', "03" },
        { '5', "04" },
        { '6', "05" },
        { '7', "06" },
        { '8', "07" },
        { '9', "08" },
        { 'T', "09" },
        { 'J', "00" },
        { 'Q', "11" },
        { 'K', "12" },
        { 'A', "13" }
    };
    
    public void Run()
    {
        //var inputLines = File.ReadAllLines("Days/Seven/Day7ExampleInput.txt");
        var inputLines = File.ReadAllLines("Days/Seven/Day7Input.txt");



        var hands = inputLines.Select(line =>
        {
            var split = line.Split(' ', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
            return new Hand(split[0],  split[1] );
        }).ToList();

        var sortedHands = hands.OrderBy(hand => hand.Score).ToList();

        long resultValue = 0;

        for (int i = 1; i < hands.Count()+1; i++)
        {
            resultValue += i * sortedHands[i-1].Bid;
        }

        Console.WriteLine("Result:" + resultValue);

    }

    public class Hand
    {
        public Hand(string cards, string bid)
        {
            Cards = cards;
            Bid = int.Parse(bid);
            Score = GenerateScore();
        }

        public string Cards { get; set; }
        public int Bid { get; set; }
        
        public long Score { get; }

        private long GenerateScore()
        {
            var generateFirstDigit = new Func(cards =>
            {
                var cardGroups = cards.GroupBy(c => c).ToList();
                var groupCounts = cardGroups.OrderByDescending(g => g.Count()).Select(g => g.Count()).ToList();
                if (cardGroups.Count() == 1)
                {
                    return 7;
                }
                else if (cardGroups.Count() == 2 && (cardGroups[0].Count() == 4 || cardGroups[0].Count() == 1))
                {
                    return 6;
                }
                else if (cardGroups.Count() == 2 && (cardGroups[0].Count() == 3 || cardGroups[0].Count() == 2))
                {
                    return 5;
                }
                else if (cardGroups.Count() == 3 && (cardGroups[0].Count() == 3 || cardGroups[1].Count() == 3 || cardGroups[2].Count() == 3))
                {
                    return 4;
                }
                else if (cardGroups.Count() == 3 && groupCounts[0] == 2 && groupCounts[1] == 2 && groupCounts[2] == 1)
                {
                    return 3;
                }
                else if (cardGroups.Count() == 4)
                {
                    return 2;
                }
                else
                {
                    return 1;
                }
            });
            
            var resultString = new StringBuilder();

            var maxFistDigit = Day7Task2.CardValues.Keys.Select(card => generateFirstDigit(Cards.Replace('J', card))).Max();

            resultString.Append(maxFistDigit);
            
            foreach (var card in Cards)
            {
                resultString.Append(Day7Task2.CardValues[card]);
            }

            Console.WriteLine("Cards:{0} Score:{1}",Cards,resultString);
            return long.Parse(resultString.ToString());
        }
    }
}

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago)

Language: Python

This was fun. More enjoyable than I initially thought (though I've done card sorting code before).

Part 1

This was pretty straightforward: create a histogram of the cards in each hand to determine their type, and if there is a tie-breaker, compare each card pairwise. I use the Counter class from collections to do the counting, and then had a dictionary/table to convert labels to numeric values for comparison. I used a very OOP approach and wrote a magic method for comparing hands and used that with Python's builtin sort. I even got to use Enum!

LABELS = {l: v for v, l in enumerate('23456789TJQKA', 2)}

class HandType(IntEnum):
    FIVE_OF_A_KIND  = 6
    FOUR_OF_A_KIND  = 5
    FULL_HOUSE      = 4
    THREE_OF_A_KIND = 3
    TWO_PAIR        = 2
    ONE_PAIR        = 1
    HIGH_CARD       = 0

class Hand:
    def __init__(self, cards=str, bid=str):
        self.cards  = cards
        self.bid    = int(bid)
        counts      = Counter(self.cards)
        self.type   = (
            HandType.FIVE_OF_A_KIND  if len(counts) == 1 else
            HandType.FOUR_OF_A_KIND  if len(counts) == 2 and any(l for l, count in counts.items() if count == 4) else
            HandType.FULL_HOUSE      if len(counts) == 2 and any(l for l, count in counts.items() if count == 3) else
            HandType.THREE_OF_A_KIND if len(counts) == 3 and any(l for l, count in counts.items() if count == 3) else
            HandType.TWO_PAIR        if len(counts) == 3 and any(l for l, count in counts.items() if count == 2) else
            HandType.ONE_PAIR        if len(counts) == 4 and any(l for l, count in counts.items() if count == 2) else
            HandType.HIGH_CARD
        )

    def __lt__(self, other):
        if self.type == other.type:
            for s_label, o_label in zip(self.cards, other.cards):
                if LABELS[s_label] == LABELS[o_label]:
                    continue
                return LABELS[s_label] < LABELS[o_label]
            return False
        return self.type < other.type

    def __repr__(self):
        return f'Hand(cards={self.cards},bid={self.bid},type={self.type})'

def read_hands(stream=sys.stdin) -> list[Hand]:
    return [Hand(*line.split()) for line in stream]

def main(stream=sys.stdin) -> None:
    hands    = sorted(read_hands(stream))
    winnings = sum(rank * hand.bid for rank, hand in enumerate(hands, 1))
    print(winnings)

Part 2

For the second part, I just had to add some post-processing code to convert the jokers into actual cards. The key insight is to find the highest and most numerous non-Joker card and convert all the Jokers to that card label.

This had two edge cases that tripped me up:

  1. 'JJJJJ': There is no other non-Joker here, so I messed up and ranked this the lowest because I ended up removing all counts.

  2. 'JJJ12': This also messed me up b/c the Joker was the most numerous card, and I didn't handle that properly.

Once I fixed the post-processing code though, everything else remained the same. Below, I only show the parts that changed from Part A.

LABELS = {l: v for v, l in enumerate('J23456789TQKA', 1)}

...

class Hand:
    def __init__(self, cards=str, bid=str):
        self.cards  = cards
        self.bid    = int(bid)
        counts      = Counter(self.cards)

        if 'J' in counts and len(counts) > 1:
            max_label = max(set(counts) - {'J'}, key=lambda l: (counts[l], LABELS[l]))
            counts[max_label] += counts['J']
            del counts['J']

        self.type   = (...)

GitHub Repo

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago)

Factor on github (with comments and imports):

! hand: "A23A4"
! card: 'Q'
! hand-bid: { "A23A4" 220 }

: card-key ( ch -- n ) "23456789TJQKA" index ;

: five-kind?  ( hand -- ? ) cardinality 1 = ;
: four-kind?  ( hand -- ? ) sorted-histogram last last 4 = ;
: full-house? ( hand -- ? ) sorted-histogram { [ last last 3 = ] [ length 2 = ] } && ;
: three-kind? ( hand -- ? ) sorted-histogram { [ last last 3 = ] [ length 3 = ] } && ;
: two-pair?   ( hand -- ? ) sorted-histogram { [ last last 2 = ] [ length 3 = ] } && ;
: one-pair?   ( hand -- ? ) sorted-histogram { [ last last 2 = ] [ length 4 = ] } && ;
: high-card?  ( hand -- ? ) cardinality 5 = ;

: type-key ( hand -- n )
  [ 0 ] dip
  { [ high-card? ] [ one-pair? ] [ two-pair? ] [ three-kind? ] [ full-house? ] [ four-kind? ] [ five-kind? ] }
  [ dup empty? ] [
    unclip pick swap call( h -- ? )
    [ drop f ] [ [ 1 + ] 2dip ] if
  ] until 2drop
;

:: (hand-compare) ( hand1 hand2 type-key-quot card-key-quot -- <=> )
  hand1 hand2 type-key-quot compare
  dup +eq+ = [
    drop hand1 hand2 [ card-key-quot compare ] { } 2map-as
    { +eq+ } without ?first
    dup [ drop +eq+ ] unless
  ] when
; inline

: hand-compare ( hand1 hand2 -- <=> ) [ type-key ] [ card-key ] (hand-compare) ;

: input>hand-bids ( -- hand-bids )
  "vocab:aoc-2023/day07/input.txt" utf8 file-lines
  [ " " split1 string>number 2array ] map
;

: solve ( hand-compare-quot -- )
  '[ [ first ] bi@ @ ] input>hand-bids swap sort-with
  [ 1 + swap last * ] map-index sum .
; inline

: part1 ( -- ) [ hand-compare ] solve ;

: card-key-wilds ( ch -- n ) "J23456789TQKA" index ;

: type-key-wilds ( hand -- n )
  [ type-key ] [ "J" within length ] bi
  2array {
    { { 0 1 } [ 1 ] }
    { { 1 1 } [ 3 ] } { { 1 2 } [ 3 ] }
    { { 2 1 } [ 4 ] } { { 2 2 } [ 5 ] }
    { { 3 1 } [ 5 ] } { { 3 3 } [ 5 ] }
    { { 4 2 } [ 6 ] } { { 4 3 } [ 6 ] }
    { { 5 1 } [ 6 ] } { { 5 4 } [ 6 ] }
    [ first ]
  } case
;

: hand-compare-wilds ( hand1 hand2 -- <=> ) [ type-key-wilds ] [ card-key-wilds ] (hand-compare) ;

: part2 ( -- ) [ hand-compare-wilds ] solve ;
[–] [email protected] 2 points 1 year ago (2 children)

This wasn't too bad. Had a worried moment when the part 2 solution took more than half a second. Maybe a better solution that brute forcing all the joker combinations, but it worked.

Python

import re
import argparse
import itertools
from enum import Enum

rule_jokers_enabled = False

class CardType(Enum):
    HighCard = 1
    OnePair = 2
    TwoPair = 3
    ThreeOfAKind = 4
    FullHouse = 5
    FourOfAKind = 6
    FiveOfAKind = 7

class Hand:
    def __init__(self,cards:str,bid:int) -> None:
        self.cards = cards
        self.bid = int(bid)
        if rule_jokers_enabled:
            self.type = self._find_type_joker(cards)
        else:
            self.type = self._find_type(cards)

    def _find_type(self,cards:str) -> CardType:
        # group cards based on card counts
        card_list = [*cards]
        card_list.sort()
        grouping = itertools.groupby(card_list,lambda x:x)
        lengths = [len(list(x[1])) for x in grouping]
        if 5 in lengths:
            return CardType.FiveOfAKind
        if 4 in lengths:
            return CardType.FourOfAKind
        if 3 in lengths and 2 in lengths:
            return CardType.FullHouse
        if 3 in lengths:
            return CardType.ThreeOfAKind
        if len([x for x in lengths if x == 2]) == 2:
            return CardType.TwoPair
        if 2 in lengths:
            return CardType.OnePair
        return CardType.HighCard
    
    def _find_type_joker(self,cards:str) -> CardType:
        try:
            joker_i = cards.index("J") 
        except ValueError:
            return self._find_type(cards)
        
        current_value = CardType.HighCard
        for new_card in [*(valid_card_list())]:
            if new_card == "J":
                continue
            test_cards = list(cards)
            test_cards[joker_i] = new_card
            new_value = self._find_type_joker("".join(test_cards))
            if new_value.value > current_value.value:
                current_value = new_value
        
        return current_value

    
    def sort_string(self):
        v = str(self.type.value) + ":" + "".join(["abcdefghijklmnoZ"[card_value(x)] for x in [*self.cards]])
        return v
    
    def __repr__(self) -> str:
        return f""



def valid_card_list() -> str:
    if rule_jokers_enabled:
        return "J23456789TQKA"
    return "23456789TJQKA"

def card_value(char:chr):
    return valid_card_list().index(char)

def main(line_list: list):
    hand_list = list()
    for l in line_list:
        card,bid = re.split(' +',l)
        hand = Hand(card,bid)
        hand_list.append(hand)
        #print(hand.sort_string())
    
    hand_list.sort(key=lambda x: x.sort_string())
    print(hand_list)

    rank_total = 0
    rank = 1
    for single_hand in hand_list:
        rank_total += rank * single_hand.bid
        rank += 1
    
    print(f"total {rank_total}")

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="day 1 solver")
    parser.add_argument("-input",type=str)
    parser.add_argument("-part",type=int)
    args = parser.parse_args()

    if args.part == 2:
        rule_jokers_enabled = True

    filename = args.input
    if filename == None:
        parser.print_help()
        exit(1)
    file = open(filename,'r')
    main([line.rstrip('\n') for line in file.readlines()])
    file.close()

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago) (1 children)

I barely registered a difference between part 1 and part 2.

Part 1: 00:00:00.0018302
Part 2: 00:00:00.0073136

I suppose it took about 3.5 times as long, but I didn't notice :P

Edit: I realize that I made the implicit assumption in my solution that it doesn't make sense to have multiple jokers be interpreted as different values. i.e., The hand with the maximum value will have all Jokers interpreted as the same other card. I think that is true though. It worked out for me anyway.

[–] [email protected] 1 points 1 year ago

Yea I was thinking there might be a simplification trick, but also figured "there can't be that many combinations right?" I suspect that was probably an intended optimisation.

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago)

I think one doesn't need to generate all combinations. All combinations using cards already present in the hand should be enough (since a joker can only increase the value of the hand by being grouped with existing cards (since in this game having four of a kind is always better than having any hand with a four of a kind/full house and having 3 is always better than any hand with pairs, and having a pair is better than any card without any cards of the same kind)). This massively decreases the amount of combinations needed to be generated per jokery hand.

[–] porotoman99 2 points 1 year ago* (last edited 1 year ago)

Python

Part 1: https://github.com/porotoman99/Advent-of-Code-2023/blob/main/Day%207/part1.py

Code

import os

filePath = os.path.dirname(os.path.realpath(__file__))
inputFilePath = filePath + "\\adventofcode.com_2023_day_7_input.txt"
# inputFilePath = filePath + "\\part1.txt"

def typeSort(hand):
	cardCount = {
		"2": 0,
		"3": 0,
		"4": 0,
		"5": 0,
		"6": 0,
		"7": 0,
		"8": 0,
		"9": 0,
		"T": 0,
		"J": 0,
		"Q": 0,
		"K": 0,
		"A": 0
	}
	for card in hand:
		cardCount[card] += 1
	cardTotals = list(cardCount.values())
	cardTotals.sort(reverse=True)
	if(cardTotals[0] == 5):
		return 6
	elif(cardTotals[0] == 4):
		return 5
	elif(cardTotals[0] == 3 and cardTotals[1] == 2):
		return 4
	elif(cardTotals[0] == 3):
		return 3
	elif(cardTotals[0] == 2 and cardTotals[1] == 2):
		return 2
	elif(cardTotals[0] == 2):
		return 1
	else:
		return 0

def bucketSort(camelCard):
	totalScore = 0
	cardOrder = ["2","3","4","5","6","7","8","9","T","J","Q","K","A"]
	hand = camelCard[0]
	totalScore += cardOrder.index(hand[4]) * 15 ** 1
	totalScore += cardOrder.index(hand[3]) * 15 ** 2
	totalScore += cardOrder.index(hand[2]) * 15 ** 3
	totalScore += cardOrder.index(hand[1]) * 15 ** 4
	totalScore += cardOrder.index(hand[0]) * 15 ** 5
	return totalScore

hands = []
bids = []

with open(inputFilePath) as inputFile:
	for line in inputFile:
		lineSplit = line.split()
		hand = lineSplit[0]
		bid = lineSplit[1]
		hands.append(hand)
		bids.append(bid)

bids = [int(bid) for bid in bids]

camelCards = list(zip(hands,bids))

typeBuckets = [[],[],[],[],[],[],[]]

for camelCard in camelCards:
	hand = camelCard[0]
	typeScore = typeSort(hand)
	typeBuckets[typeScore].append(camelCard)

finalCardSort = []

for bucket in typeBuckets:
	if(len(bucket) > 1):
		bucket.sort(key=bucketSort)
	for camelCard in bucket:
		finalCardSort.append(camelCard)

camelScores = []

for camelIndex in range(len(finalCardSort)):
	scoreMultiplier = camelIndex + 1
	camelCard = finalCardSort[camelIndex]
	camelScores.append(camelCard[1] * scoreMultiplier)

print(sum(camelScores))

Part 2: https://github.com/porotoman99/Advent-of-Code-2023/blob/main/Day%207/part2.py

Code

import os

filePath = os.path.dirname(os.path.realpath(__file__))
inputFilePath = filePath + "\\adventofcode.com_2023_day_7_input.txt"
# inputFilePath = filePath + "\\part1.txt"

def typeSort(hand):
	cardCount = {
		"J": 0,
		"2": 0,
		"3": 0,
		"4": 0,
		"5": 0,
		"6": 0,
		"7": 0,
		"8": 0,
		"9": 0,
		"T": 0,
		"Q": 0,
		"K": 0,
		"A": 0
	}
	for card in hand:
		cardCount[card] += 1
	jokerCount = cardCount["J"]
	cardCount["J"] = 0
	cardTotals = list(cardCount.values())
	cardTotals.sort(reverse=True)
	if(cardTotals[0] + jokerCount == 5):
		return 6
	elif(cardTotals[0] + jokerCount == 4):
		return 5
	elif(
		cardTotals[0] + jokerCount == 3 and cardTotals[1] == 2
		or cardTotals[0] == 3 and cardTotals[1] + jokerCount == 2
	):
		return 4
	elif(cardTotals[0] + jokerCount == 3):
		return 3
	elif(
		cardTotals[0] + jokerCount == 2 and cardTotals[1] == 2
		or cardTotals[0] == 2 and cardTotals[1] + jokerCount == 2
	):
		return 2
	elif(cardTotals[0] + jokerCount == 2):
		return 1
	else:
		return 0

def bucketSort(camelCard):
	totalScore = 0
	cardOrder = ["J","2","3","4","5","6","7","8","9","T","Q","K","A"]
	hand = camelCard[0]
	totalScore += cardOrder.index(hand[4]) * 15 ** 1
	totalScore += cardOrder.index(hand[3]) * 15 ** 2
	totalScore += cardOrder.index(hand[2]) * 15 ** 3
	totalScore += cardOrder.index(hand[1]) * 15 ** 4
	totalScore += cardOrder.index(hand[0]) * 15 ** 5
	return totalScore

hands = []
bids = []

with open(inputFilePath) as inputFile:
	for line in inputFile:
		lineSplit = line.split()
		hand = lineSplit[0]
		bid = lineSplit[1]
		hands.append(hand)
		bids.append(bid)

bids = [int(bid) for bid in bids]

camelCards = list(zip(hands,bids))

typeBuckets = [[],[],[],[],[],[],[]]

for camelCard in camelCards:
	hand = camelCard[0]
	typeScore = typeSort(hand)
	typeBuckets[typeScore].append(camelCard)

finalCardSort = []

for bucket in typeBuckets:
	if(len(bucket) > 1):
		bucket.sort(key=bucketSort)
	for camelCard in bucket:
		finalCardSort.append(camelCard)

camelScores = []

for camelIndex in range(len(finalCardSort)):
	scoreMultiplier = camelIndex + 1
	camelCard = finalCardSort[camelIndex]
	camelScores.append(camelCard[1] * scoreMultiplier)

print(sum(camelScores))

I tried to do this one as quickly as possible, so the code is more messy than I would prefer, but it works, and I don't think the solution is too bad overall.

Edit: I went back and changed it to be a bit better. Here are my new solutions:

Part 1 v2: https://github.com/porotoman99/Advent-of-Code-2023/blob/main/Day%207/part1v2.py

Code

import os

filePath = os.path.dirname(os.path.realpath(__file__))
inputFilePath = filePath + "\\adventofcode.com_2023_day_7_input.txt"
# inputFilePath = filePath + "\\part1.txt"

CARD_ORDER = "23456789TJQKA"

def typeSort(camelCard):
	cardCount = {}
	for card in CARD_ORDER:
		cardCount[card] = 0
	hand = camelCard[0]
	for card in hand:
		cardCount[card] += 1
	cardTotals = list(cardCount.values())
	cardTotals.sort(reverse=True)
	if(cardTotals[0] == 5):
		return 6
	elif(cardTotals[0] == 4):
		return 5
	elif(cardTotals[0] == 3 and cardTotals[1] == 2):
		return 4
	elif(cardTotals[0] == 3):
		return 3
	elif(cardTotals[0] == 2 and cardTotals[1] == 2):
		return 2
	elif(cardTotals[0] == 2):
		return 1
	else:
		return 0

def handSort(camelCard):
	totalScore = 0
	hand = camelCard[0]
	totalScore += CARD_ORDER.index(hand[4]) * 15 ** 1
	totalScore += CARD_ORDER.index(hand[3]) * 15 ** 2
	totalScore += CARD_ORDER.index(hand[2]) * 15 ** 3
	totalScore += CARD_ORDER.index(hand[1]) * 15 ** 4
	totalScore += CARD_ORDER.index(hand[0]) * 15 ** 5
	return totalScore

hands = []
bids = []

with open(inputFilePath) as inputFile:
	for line in inputFile:
		lineSplit = line.split()
		hand = lineSplit[0]
		bid = lineSplit[1]
		hands.append(hand)
		bids.append(int(bid))

camelCards = list(zip(hands,bids))
camelCards = sorted(camelCards, key=lambda x: (typeSort(x), handSort(x)))

camelScores = []

for camelIndex in range(len(camelCards)):
	scoreMultiplier = camelIndex + 1
	camelCard = camelCards[camelIndex]
	camelScores.append(camelCard[1] * scoreMultiplier)

print(sum(camelScores))

Part 2 v2: https://github.com/porotoman99/Advent-of-Code-2023/blob/main/Day%207/part2v2.py

Code

import os

filePath = os.path.dirname(os.path.realpath(__file__))
inputFilePath = filePath + "\\adventofcode.com_2023_day_7_input.txt"
# inputFilePath = filePath + "\\part1.txt"

CARD_ORDER = "J23456789TQKA"

def typeSort(camelCard):
	cardCount = {}
	for card in CARD_ORDER:
		cardCount[card] = 0
	hand = camelCard[0]
	for card in hand:
		cardCount[card] += 1
	jokerCount = cardCount["J"]
	cardCount["J"] = 0
	cardTotals = list(cardCount.values())
	cardTotals.sort(reverse=True)
	if(cardTotals[0] + jokerCount == 5):
		return 6
	elif(cardTotals[0] + jokerCount == 4):
		return 5
	elif(
		cardTotals[0] + jokerCount == 3 and cardTotals[1] == 2
		or cardTotals[0] == 3 and cardTotals[1] + jokerCount == 2
	):
		return 4
	elif(cardTotals[0] + jokerCount == 3):
		return 3
	elif(
		cardTotals[0] + jokerCount == 2 and cardTotals[1] == 2
		or cardTotals[0] == 2 and cardTotals[1] + jokerCount == 2
	):
		return 2
	elif(cardTotals[0] + jokerCount == 2):
		return 1
	else:
		return 0

def handSort(camelCard):
	totalScore = 0
	hand = camelCard[0]
	totalScore += CARD_ORDER.index(hand[4]) * 15 ** 1
	totalScore += CARD_ORDER.index(hand[3]) * 15 ** 2
	totalScore += CARD_ORDER.index(hand[2]) * 15 ** 3
	totalScore += CARD_ORDER.index(hand[1]) * 15 ** 4
	totalScore += CARD_ORDER.index(hand[0]) * 15 ** 5
	return totalScore

hands = []
bids = []

with open(inputFilePath) as inputFile:
	for line in inputFile:
		lineSplit = line.split()
		hand = lineSplit[0]
		bid = lineSplit[1]
		hands.append(hand)
		bids.append(int(bid))

camelCards = list(zip(hands,bids))
camelCards = sorted(camelCards, key=lambda x: (typeSort(x), handSort(x)))

camelScores = []

for camelIndex in range(len(camelCards)):
	scoreMultiplier = camelIndex + 1
	camelCard = camelCards[camelIndex]
	camelScores.append(camelCard[1] * scoreMultiplier)

print(sum(camelScores))

[–] landreville 2 points 1 year ago* (last edited 1 year ago)

My solution in Rust.

Took me way too long to realize I could simply add jokers to the count of the most common card in the hand.

[–] [email protected] 2 points 1 year ago

[language: Lean4]

As with the previous days: I'll only post the solution and parsing, not the dependencies I've put into separate files. For the full source code, please see github.

The key idea for part 2 was that

Spoilerit doesn't make any sense to pick different cards for the jokers, and that it's always the highest score to assign all jokers to the most frequent card.

Solution

inductive Card
  | two
  | three
  | four
  | five
  | six
  | seven
  | eight
  | nine
  | ten
  | jack
  | queen
  | king
  | ace
  deriving Repr, Ord, BEq

inductive Hand
  | mk : Card β†’ Card β†’ Card β†’ Card β†’ Card β†’ Hand
  deriving Repr, BEq

private inductive Score
  | highCard
  | onePair
  | twoPair
  | threeOfAKind
  | fullHouse
  | fourOfAKind
  | fiveOfAKind
  deriving Repr, Ord, BEq

-- we need countCards in part 2 again, but there it has different types
private class CardList (Ξ· : Type) (Ο‡ : outParam Type) where
  cardList : Ξ· β†’ List Ο‡

-- similarly, we can implement Ord in terms of CardList and Score
private class Scorable (Ξ· : Type) where
  score : Ξ· β†’ Score

private instance : CardList Hand Card where
  cardList := Ξ»
    | .mk a b c d e => [a,b,c,d,e]

private def countCards {Ξ· Ο‡ : Type} (input :Ξ·) [CardList Ξ· Ο‡] [Ord Ο‡] [BEq Ο‡] : List (Nat Γ— Ο‡) :=
  let ordered := (CardList.cardList input).quicksort
  let helper := Ξ» (a : List (Nat Γ— Ο‡)) (c : Ο‡) ↦ match a with
  | [] => [(1, c)]
  | a :: as =>
    if a.snd == c then
      (a.fst + 1, c) :: as
    else
      (1, c) :: a :: as
  List.quicksortBy (Β·.fst > Β·.fst) $ ordered.foldl helper []

private def evaluateCountedCards : (l : List (Nat Γ— Ξ±)) β†’ Score
  | [_] => Score.fiveOfAKind -- only one entry means all cards are equal
  | (4,_) :: _ => Score.fourOfAKind
  | [(3,_), (2,_)] => Score.fullHouse
  | (3,_) :: _ => Score.threeOfAKind
  | [(2,_), (2,_), _] => Score.twoPair
  | (2,_) :: _ => Score.onePair
  | _ => Score.highCard

private def Hand.score (hand : Hand) : Score :=
  evaluateCountedCards $ countCards hand

private instance : Scorable Hand where
  score := Hand.score

instance {Οƒ Ο‡ : Type} [Scorable Οƒ] [CardList Οƒ Ο‡] [Ord Ο‡] : Ord Οƒ where
  compare (a b : Οƒ) :=
    let comparedScores := Ord.compare (Scorable.score a) (Scorable.score b)
    if comparedScores != Ordering.eq then
      comparedScores
    else
      Ord.compare (CardList.cardList a) (CardList.cardList b)

private def Card.fromChar? : Char β†’ Option Card
| '2' => some Card.two
| '3' => some Card.three
| '4' => some Card.four
| '5' => some Card.five
| '6' => some Card.six
| '7' => some Card.seven
| '8' => some Card.eight
| '9' => some Card.nine
| 'T' => some Card.ten
| 'J' => some Card.jack
| 'Q' => some Card.queen
| 'K' => some Card.king
| 'A' => some Card.ace
| _ => none

private def Hand.fromString? (input : String) : Option Hand :=
  match input.toList.mapM Card.fromChar? with
  | some [a, b, c, d, e] => Hand.mk a b c d e
  | _ => none

abbrev Bet := Nat

structure Player where
  hand : Hand
  bet : Bet
  deriving Repr

def parse (input : String) : Except String (List Player) := do
  let lines := input.splitOn "\n" |> List.map String.trim |> List.filter String.notEmpty
  let parseLine := Ξ» (line : String) ↦
    if let [hand, bid] := line.split Char.isWhitespace |> List.map String.trim |> List.filter String.notEmpty then
      Option.zip (Hand.fromString? hand) (String.toNat? bid)
      |> Option.map (uncurry Player.mk)
      |> Option.toExcept s!"Line could not be parsed: {line}"
    else
      throw s!"Failed to parse. Line did not separate into hand and bid properly: {line}"
  lines.mapM parseLine

def part1 (players : List Player) : Nat :=
  players.quicksortBy (Ξ» p q ↦ p.hand < q.hand)
  |> List.enumFrom 1
  |> List.foldl (Ξ» r p ↦ p.fst * p.snd.bet + r) 0


------------------------------------------------------------------------------------------------------
-- Again a riddle where part 2 needs different data representation, why are you doing this to me? Why?
-- (Though, strictly speaking, I could just add "joker" to the list of cards in part 1 and treat it special)

private inductive Card2
  | joker
  | two
  | three
  | four
  | five
  | six
  | seven
  | eight
  | nine
  | ten
  | queen
  | king
  | ace
  deriving Repr, Ord, BEq

private def Card.toCard2 : Card β†’ Card2
  | .two => Card2.two
  | .three => Card2.three
  | .four => Card2.four
  | .five => Card2.five
  | .six => Card2.six
  | .seven => Card2.seven
  | .eight => Card2.eight
  | .nine => Card2.nine
  | .ten => Card2.ten
  | .jack => Card2.joker
  | .queen => Card2.queen
  | .king => Card2.king
  | .ace => Card2.ace

private inductive Hand2
  | mk : Card2 β†’ Card2 β†’ Card2 β†’ Card2 β†’ Card2 β†’ Hand2
  deriving Repr

private def Hand.toHand2 : Hand β†’ Hand2
  | Hand.mk a b c d e => Hand2.mk a.toCard2 b.toCard2 c.toCard2 d.toCard2 e.toCard2

instance : CardList Hand2 Card2 where
  cardList := Ξ»
    | .mk a b c d e => [a,b,c,d,e]

private def Hand2.score (hand : Hand2) : Score :=
  -- I could be dumb here and just let jokers be any other card, but that would be really wasteful
  -- Also, I'm pretty sure there is no combination that would benefit from jokers being mapped to
  -- different cards.
  -- and, even more important, I think we can always map jokers to the most frequent card and are
  -- still correct.
  let counted := countCards hand
  let (jokers, others) := counted.partition Ξ» e ↦ e.snd == Card2.joker
  let jokersReplaced := match jokers, others with
  | (jokers, _) :: _ , (a, ac) :: as => (a+jokers, ac) :: as
  | _ :: _, [] => jokers
  | [], others => others
  evaluateCountedCards jokersReplaced

private instance : Scorable Hand2 where
  score := Hand2.score

private structure Player2 where
  bet : Bet
  hand2 : Hand2

def part2 (players : List Player) : Nat :=
  let players := players.map Ξ» p ↦
    {bet := p.bet, hand2 := p.hand.toHand2 : Player2}
  players.quicksortBy (Ξ» p q ↦ p.hand2 < q.hand2)
  |> List.enumFrom 1
  |> List.foldl (Ξ» r p ↦ p.fst * p.snd.bet + r) 0

[–] [email protected] 1 points 1 year ago* (last edited 4 months ago) (1 children)

Python

import collections

from .solver import Solver

_FIVE_OF_A_KIND  = 0x100000
_FOUR_OF_A_KIND  = 0x010000
_FULL_HOUSE      = 0x001000
_THREE_OF_A_KIND = 0x000100
_TWO_PAIR        = 0x000010
_ONE_PAIR        = 0x000001

_CARD_ORDER            = '23456789TJQKA'
_CARD_ORDER_WITH_JOKER = 'J23456789TQKA'

def evaluate_hand(hand: str, joker: bool = False) -> int:
  card_counts = collections.defaultdict(int)
  score = 0
  for card in hand:
    card_counts[card] += 1
  joker_count = 0
  if joker:
    joker_count = card_counts['J']
    del card_counts['J']
  counts = sorted(card_counts.values(), reverse=True)
  top_non_joker_count = counts[0] if counts else 0
  if top_non_joker_count + joker_count == 5:
    score |= _FIVE_OF_A_KIND
  elif top_non_joker_count + joker_count == 4:
    score |= _FOUR_OF_A_KIND
  elif top_non_joker_count + joker_count == 3:
    match counts, joker_count:
      case [3, 2], 0:
        score |= _FULL_HOUSE
      case [3, 1, 1], 0:
        score |= _THREE_OF_A_KIND
      case [2, 2], 1:
        score |= _FULL_HOUSE
      case [2, 1, 1], 1:
        score |= _THREE_OF_A_KIND
      case [1, 1, 1], 2:
        score |= _THREE_OF_A_KIND
      case _:
        raise RuntimeError(f'Unexpected card counts: {counts} with {joker_count} jokers')
  elif top_non_joker_count + joker_count == 2:
    match counts, joker_count:
      case [2, 2, 1], 0:
        score |= _TWO_PAIR
      case [2, 1, 1, 1], 0:
        score |= _ONE_PAIR
      case [1, 1, 1, 1], 1:
        score |= _ONE_PAIR
      case _:
        raise RuntimeError(f'Unexpected card counts: {counts} with {joker_count} jokers')
  card_order = _CARD_ORDER_WITH_JOKER if joker else _CARD_ORDER
  for card in hand:
    card_value = card_order.index(card)
    score <<= 4
    score |= card_value
  return score

class Day07(Solver):

  def __init__(self):
    super().__init__(7)
    self.hands: list[tuple[str, str]] = []

  def presolve(self, input: str):
    lines = input.rstrip().split('\n')
    self.hands = list(map(lambda line: line.split(' '), lines))

  def solve_first_star(self):
    hands = self.hands[:]
    hands.sort(key=lambda hand: evaluate_hand(hand[0]))
    total_score = 0
    for rank, [_, bid] in enumerate(hands):
      total_score += (rank + 1) * int(bid)
    return total_score

  def solve_second_star(self):
    hands = self.hands[:]
    hands.sort(key=lambda hand: evaluate_hand(hand[0], True))
    total_score = 0
    for rank, [_, bid] in enumerate(hands):
      total_score += (rank + 1) * int(bid)
    return total_score
[–] [email protected] 1 points 1 year ago (1 children)

Oh boy. bitwise nonsense. Ok, can you explain it to me? I'm terrible at bitwise stuff.

[–] [email protected] 3 points 1 year ago (2 children)

Sure! This generates a number for every hand, so that a better hand gets a higher number. The resulting number will contain 11 hexadecimal digits:

0x100000 bbbbb
  ^^^^^^ \____ the hand itself
  |||||\_ 1 if "one pair"
  ||||\__ 1 if "two pairs"
  |||\___ 1 if "three of a kind"
  ||\____ 1 if "full house"
  |\_____ 1 if "four of a kind"
  \______ 1 if "five of a kind"

For example:
 AAAAA: 0x100000 bbbbb
 AAAA2: 0x010000 bbbb0
 22233: 0x001000 00011

The hand itself is 5 hexadecimal digits for every card, 0 for "2" to b for "ace".

This way the higher combination always has a higher number, and hands with the same combination are ordered by the order of the cards in the hand.

[–] [email protected] 2 points 1 year ago (1 children)

That is a really cool solution. Thanks for the explanation! I took a much more... um... naive path lol.

[–] [email protected] 2 points 1 year ago (1 children)

I think you have the same solution, basically, just the details are a bit different. I like how you handled the joker, I didn't realise you could just multiply your best streak of cards to get the best possible combination.

[–] [email protected] 1 points 1 year ago (1 children)

I didn't multiply the streak, I just took the jokers and added them to the highest hand already in the list. Is that not what you did? It looked the same to me.

[–] [email protected] 1 points 1 year ago

This is what I meant, but I phrased it poorly :)

In my solution I reimplement the logic of identifying the hand value, but with the presence of joker (instead of just reusing the same logic).

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago) (1 children)

Wow, this is exactly what I did, but in C#. That's cool.

    public class Hand
    {
        public string Cards;
        public int Rank;
        public int Bid;
    }

    public static HandType IdentifyHandType(string hand)
    {
        var cardCounts = hand
            .Aggregate(
                new Dictionary(),
                (counts, card) => 
                {
                    counts[card] = counts.TryGetValue(card, out var count) ? (count + 1) : 1;
                    return counts;
                })
            .OrderByDescending(kvp => kvp.Value);

        using (var cardCount = cardCounts.GetEnumerator())
        {
            cardCount.MoveNext();
            switch (cardCount.Current.Value)
            {
                case 5: return HandType.FiveOfAKind;
                case 4: return HandType.FourOfAKind;
                case 3: { cardCount.MoveNext(); return (cardCount.Current.Value == 2) ? HandType.FullHouse : HandType.ThreeOfAKind; }
                case 2: { cardCount.MoveNext(); return (cardCount.Current.Value == 2) ? HandType.TwoPairs : HandType.OnePair; }
            }
        }

        return HandType.HighCard;
    }

    public static Hand SetHandRank(Hand hand, Dictionary cardValues)
    {
        int rank = 0;
        int offset = 0;

        var cardValueHand = hand.Cards;
        for (int i = cardValueHand.Length - 1; i >= 0; i--)
        {
            var card = cardValueHand[i];
            var cardValue = cardValues[card];
            var offsetCardValue = cardValue << offset;
            rank |= offsetCardValue;
            offset += 4; // To store values up to 13 we need 4 bits.
        }

        // Put the hand type at the high end because it is the most
        // important factor in the rank.
        var handType = (int)IdentifyHandType(hand.Cards);
        var offsetHandType = handType << offset;
        rank |= offsetHandType;

        hand.Rank = rank;
        return hand;
    }
[–] [email protected] 1 points 1 year ago* (last edited 1 year ago)

JavaScript

Ended up misreading the instructions due to trying to go fast. Built up a system to compare hand values like its poker before I realized its not poker

Likely last day im going to be able to write code for due to exams coming up

Code Link

Code Block

// Part 1
// ======

function part1(input) {
  const lines = input.replaceAll("\r", "").split("\n");
  const hands = lines.map((line) => line.split(" "));

  const sortedHands = hands.sort((a, b) => {
    const handA = calculateHandValue(a[0]);
    const handB = calculateHandValue(b[0]);

    if (handA > handB) {
      return -1;
    } else if (handA < handB) {
      return 1;
    } else {
      for (let i = 0; i < 5; i++) {
        const handACard = convertToNumber(a[0].split("")[i]);
        const handBCard = convertToNumber(b[0].split("")[i]);
        if (handACard > handBCard) {
          return 1;
        } else if (handACard < handBCard) {
          return -1;
        }
      }
    }
  });

  return sortedHands
    .filter((hand) => hand[0] != "")
    .reduce((acc, hand, i) => {
      return acc + hand[1] * (i + 1);
    }, 0);
}

function convertToNumber(card) {
  switch (card) {
    case "A":
      return 14;
    case "K":
      return 13;
    case "Q":
      return 12;
    case "J":
      return 11;
    case "T":
      return 10;
    default:
      return parseInt(card);
  }
}

function calculateHandValue(hand) {
  const dict = {};

  hand.split("").forEach((card) => {
    if (dict[card]) {
      dict[card] += 1;
    } else {
      dict[card] = 1;
    }
  });

  // 5
  if (Object.keys(dict).length === 1) {
    return 1;
  }

  // 4
  if (Object.keys(dict).filter((key) => dict[key] === 4).length === 1) {
    return 2;
  }

  // 3 + 2
  if (
    Object.keys(dict).filter((key) => dict[key] === 3).length === 1 &&
    Object.keys(dict).filter((key) => dict[key] === 2).length === 1
  ) {
    return 3;
  }

  // 3
  if (Object.keys(dict).filter((key) => dict[key] === 3).length === 1) {
    return 4;
  }

  // 2 + 2
  if (Object.keys(dict).filter((key) => dict[key] === 2).length === 2) {
    return 5;
  }

  // 2
  if (Object.keys(dict).filter((key) => dict[key] === 2).length === 1) {
    return 6;
  }

  return 7;
}

// Part 2
// ======

function part2(input) {
  const lines = input.replaceAll("\r", "").split("\n");
  const hands = lines.map((line) => line.split(" "));

  const sortedHands = hands.sort((a, b) => {
    const handA = calculateHandValuePart2(a[0]);
    const handB = calculateHandValuePart2(b[0]);

    if (handA > handB) {
      return -1;
    } else if (handA < handB) {
      return 1;
    } else {
      for (let i = 0; i < 5; i++) {
        const handACard = convertToNumberPart2(a[0].split("")[i]);
        const handBCard = convertToNumberPart2(b[0].split("")[i]);
        if (handACard > handBCard) {
          return 1;
        } else if (handACard < handBCard) {
          return -1;
        }
      }
    }
  });

  return sortedHands
    .filter((hand) => hand[0] != "")
    .reduce((acc, hand, i) => {
      console.log(acc, hand, i + 1);
      return acc + hand[1] * (i + 1);
    }, 0);
}

function convertToNumberPart2(card) {
  switch (card) {
    case "A":
      return 14;
    case "K":
      return 13;
    case "Q":
      return 12;
    case "J":
      return 1;
    case "T":
      return 10;
    default:
      return parseInt(card);
  }
}

function calculateHandValuePart2(hand) {
  const dict = {};

  let jokers = 0;

  hand.split("").forEach((card) => {
    if (card === "J") {
      jokers += 1;
      return;
    }
    if (dict[card]) {
      dict[card] += 1;
    } else {
      dict[card] = 1;
    }
  });

  // 5
  if (jokers === 5 || Object.keys(dict).length === 1) {
    return 1;
  }

  // 4
  if (
    jokers === 4 ||
    (jokers === 3 &&
      Object.keys(dict).filter((key) => dict[key] === 1).length >= 1) ||
    (jokers === 2 &&
      Object.keys(dict).filter((key) => dict[key] === 2).length === 1) ||
    (jokers === 1 &&
      Object.keys(dict).filter((key) => dict[key] === 3).length === 1) ||
    Object.keys(dict).filter((key) => dict[key] === 4).length === 1
  ) {
    return 2;
  }

  // 3 + 2
  if (
    (Object.keys(dict).filter((key) => dict[key] === 3).length === 1 &&
      Object.keys(dict).filter((key) => dict[key] === 2).length === 1) ||
    (Object.keys(dict).filter((key) => dict[key] === 2).length === 2 &&
      jokers === 1)
  ) {
    return 3;
  }

  // 3
  if (
    Object.keys(dict).filter((key) => dict[key] === 3).length === 1 ||
    (Object.keys(dict).filter((key) => dict[key] === 2).length === 1 &&
      jokers === 1) ||
    (Object.keys(dict).filter((key) => dict[key] === 1).length >= 1 &&
      jokers === 2) ||
    jokers === 3
  ) {
    return 4;
  }

  // 2 + 2
  if (
    Object.keys(dict).filter((key) => dict[key] === 2).length === 2 ||
    (Object.keys(dict).filter((key) => dict[key] === 2).length === 1 &&
      jokers === 1)
  ) {
    return 5;
  }

  // 2
  if (
    Object.keys(dict).filter((key) => dict[key] === 2).length === 1 ||
    jokers
  ) {
    return 6;
  }

  return 7;
}

export default { part1, part2 };

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago)

Part 1, in C. This took me way too long, there were so many bugs and problems I overlooked. So it's very long.

https://git.sr.ht/~aidenisik/aoc23/tree/master/item/day7

EDIT: And part 2

[–] [email protected] 1 points 1 year ago

Two days, a few failed solutions, some misread instructions, and a lot of manually parsing output data and debugging silly tiny mistakes... but it's finally done. I don't really wanna talk about it.

https://github.com/capitalpb/advent_of_code_2023/blob/main/src/solvers/day07.rs

use crate::Solver;
use itertools::Itertools;
use std::cmp::Ordering;

#[derive(Clone, Copy)]
enum JType {
    Jokers = 1,
    Jacks = 11,
}

#[derive(Debug, PartialEq, Eq, PartialOrd, Ord)]
enum HandType {
    HighCard,
    OnePair,
    TwoPair,
    ThreeOfAKind,
    FullHouse,
    FourOfAKind,
    FiveOfAKind,
}

#[derive(Debug, Eq, PartialEq)]
struct CardHand {
    hand: Vec,
    bid: u64,
    hand_type: HandType,
}

impl CardHand {
    fn from(input: &str, j_type: JType) -> CardHand {
        let (hand, bid) = input.split_once(' ').unwrap();

        let hand = hand
            .chars()
            .map(|card| match card {
                '2'..='9' => card.to_digit(10).unwrap() as u64,
                'T' => 10,
                'J' => j_type as u64,
                'Q' => 12,
                'K' => 13,
                'A' => 14,
                _ => unreachable!("malformed input"),
            })
            .collect::>();

        let bid = bid.parse::().unwrap();

        let counts = hand.iter().counts();
        let hand_type = match counts.len() {
            1 => HandType::FiveOfAKind,
            2 => {
                if hand.contains(&1) {
                    HandType::FiveOfAKind
                } else {
                    if counts.values().contains(&4) {
                        HandType::FourOfAKind
                    } else {
                        HandType::FullHouse
                    }
                }
            }
            3 => {
                if counts.values().contains(&3) {
                    if hand.contains(&1) {
                        HandType::FourOfAKind
                    } else {
                        HandType::ThreeOfAKind
                    }
                } else {
                    if counts.get(&1) == Some(&2) {
                        HandType::FourOfAKind
                    } else if counts.get(&1) == Some(&1) {
                        HandType::FullHouse
                    } else {
                        HandType::TwoPair
                    }
                }
            }
            4 => {
                if hand.contains(&1) {
                    HandType::ThreeOfAKind
                } else {
                    HandType::OnePair
                }
            }
            _ => {
                if hand.contains(&1) {
                    HandType::OnePair
                } else {
                    HandType::HighCard
                }
            }
        };

        CardHand {
            hand,
            bid,
            hand_type,
        }
    }
}

impl PartialOrd for CardHand {
    fn partial_cmp(&self, other: &Self) -> Option {
        Some(self.cmp(other))
    }
}

impl Ord for CardHand {
    fn cmp(&self, other: &Self) -> Ordering {
        let hand_type_cmp = self.hand_type.cmp(&other.hand_type);

        if hand_type_cmp != Ordering::Equal {
            return hand_type_cmp;
        } else {
            for i in 0..5 {
                let value_cmp = self.hand[i].cmp(&other.hand[i]);
                if value_cmp != Ordering::Equal {
                    return value_cmp;
                }
            }
        }

        Ordering::Equal
    }
}

pub struct Day07;

impl Solver for Day07 {
    fn star_one(&self, input: &str) -> String {
        input
            .lines()
            .map(|line| CardHand::from(line, JType::Jacks))
            .sorted()
            .enumerate()
            .map(|(index, hand)| hand.bid * (index as u64 + 1))
            .sum::()
            .to_string()
    }

    fn star_two(&self, input: &str) -> String {
        input
            .lines()
            .map(|line| CardHand::from(line, JType::Jokers))
            .sorted()
            .enumerate()
            .map(|(index, hand)| hand.bid * (index as u64 + 1))
            .sum::()
            .to_string()
    }
}