Day 4: Scratchcards


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  • Nighed@sffa.community
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    edit-2
    11 months 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;
            }
        }