Day 4: Scratchcards

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    • @[email protected]English
      1•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;
        }
    }