Day 4: Scratchcards
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3 points
Ruby
Somehow took way longer on the second part than the first part trying a recursive approach and then realizing that was dumb.
https://github.com/snowe2010/advent-of-code/blob/master/ruby_aoc/2023/day04/day04.rb
1 point
*
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;
}
}