this post was submitted on 04 Dec 2023
24 points (100.0% liked)

Advent Of Code

805 readers
10 users here now

An unofficial home for the advent of code community on programming.dev!

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

Solution Threads

M T W T F S S
1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 18 20 21 22
23 24 25

Rules/Guidelines

Relevant Communities

Relevant Links

Credits

Icon base by Lorc under CC BY 3.0 with modifications to add a gradient

console.log('Hello World')

founded 1 year ago
MODERATORS
 

Day 4: Scratchcards


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/ or pastebin (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)

FAQ


🔒This post will be unlocked when there is a decent amount of submissions on the leaderboard to avoid cheating for top spots

🔓 Unlocked after 8 mins

you are viewing a single comment's thread
view the rest of the comments
[–] Nighed@sffa.community 1 points 1 year ago* (last edited 1 year ago)

Edit: Sorry, should have read your code first, you made it work too. if it works it works, Recursive solutions just click for me over other solutions.

I made the recursion work, went to a depth of 24 for my input set.

Recursive C#

internal class Day4Task2 : IRunnable
    {
        private Regex _regex = new Regex("Card\\s*\\d*: ([\\d\\s]{2} )*\\|( [\\d\\s]{2})*");
        private Dictionary _matchCountCache = new Dictionary();
        private int _maxDepth = 0;

        public void Run()
        {
            var inputLines = File.ReadAllLines("Days/Four/Day4Input.txt");
            int sumScore = 0;

            for (int i = 0; i < inputLines.Length; i++)
            {
                sumScore += ScoreCard(i, inputLines, 0);
                Console.WriteLine("!!!" + i + "!!!");
            }

            Console.WriteLine("Sum:"+sumScore.ToString());
            Console.WriteLine("Max Recursion Depth:"+ _maxDepth.ToString());
        }

        private int ScoreCard(int lineId, string[] inputLines, int depth)
        {
            if( depth > _maxDepth )
            {
                _maxDepth = depth;
            }

            if(lineId >= inputLines.Length)
            {
                return 0;
            }

            int matchCount = 0;

            if (!_matchCountCache.ContainsKey(lineId)) {

                var winningSet = new HashSet();
                var matches = _regex.Match(inputLines[lineId]);
                foreach (Capture capture in matches.Groups[1].Captures)
                {
                    winningSet.Add(capture.Value.Trim());
                }

                foreach (Capture capture in matches.Groups[2].Captures)
                {
                    if (winningSet.Contains(capture.Value.Trim()))
                    {
                        matchCount++;
                    }
                }

                _matchCountCache[lineId] = matchCount;
            }

            matchCount = _matchCountCache[lineId];

            int totalCards = 1;
            while(matchCount > 0)
            {
                totalCards += ScoreCard(lineId+matchCount, inputLines, depth+1);
                matchCount--;
            }
            //Console.WriteLine("Finished processing id: " + lineId + " Sum is: " + totalCards);
            return totalCards;
        }
    }