Initial Commit

2025-11-30 20:28:10 -05:00
commit e9ac699e67
209 changed files with 39737 additions and 0 deletions
--- a/2023/Day04CSharp/Program.cs
+++ b/2023/Day04CSharp/Program.cs
@@ -0,0 +1,151 @@
+// See https://aka.ms/new-console-template for more information
+using AdventCommon;
+
+int p1exampleSln = Part01("example-input.txt");
+int p1puzzleSln = Part01("puzzle-input.txt");
+
+Console.WriteLine("Part01 Example Points: " + p1exampleSln);
+Console.WriteLine("Part01 Puzzle Points: " + p1puzzleSln);
+
+int p2exampleSln = Part02("example-input.txt");
+int p2puzzleSln = Part02("puzzle-input.txt");
+
+Console.WriteLine("Part02 Example Points: " + p2exampleSln);
+Console.WriteLine("Part02 Puzzle Points: " + p2puzzleSln);
+
+int Part01(string fileName)
+{
+    var input = new Day04Input(fileName);
+
+    int sum = 0;
+    foreach (var c in input.Cards)
+    {
+        sum += c.Points;
+    }
+
+    return sum;
+}
+
+int Part02(string fileName)
+{
+    var input = new Day04Input(fileName);
+
+    Dictionary<int, int>    CardCopies = new Dictionary<int, int>();
+
+    // Initial state -- 1 of each
+    for (int i = 0;  i < input.Cards.Count; i++)
+    {
+        CardCopies.Add(i + 1, 1);
+    }
+
+    // Start with card 1 and work to the end
+    for (int i = 0; i < input.Cards.Count; i++)
+    {
+        Day04Input.Card card = input.GetCardNumber(i + 1);
+        int numberOfCards = CardCopies[i + 1];
+        var matches = card.MatchingNumbers;
+
+        for (int cardNum = 0; cardNum < numberOfCards; cardNum++)
+        {
+            for (int j = 0; j < matches.Count; j++)
+            {
+                CardCopies[i + 2 + j]++;
+            }
+        }
+    }
+
+    int sum = 0;
+    foreach (var c in CardCopies)
+    {
+        sum += c.Value;
+    }
+    
+    return sum;
+}
+
+class Day04Input : PuzzleInput
+{
+    public class Card
+    {
+        public List<int>    WinningNumbers { get; private set; } = new List<int>();
+        public List<int>    ScratchedNumbers { get; private set; } = new List<int> ();
+        public int          CardNumber { get; private set; }
+
+        public Card(string line)
+        {
+            // Extract card number
+            CardNumber = Int32.Parse(line.Split(':', StringSplitOptions.RemoveEmptyEntries)[0].Split(' ', StringSplitOptions.RemoveEmptyEntries)[1]);
+
+            // extract numbers
+            string winningNumbers = line.Split(":")[1].Split('|', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)[0];
+            string scratchedNumbers = line.Split(":")[1].Split('|', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)[1];
+
+            // parse the winning numbers
+            foreach (var winningNumber in winningNumbers.Split(' ', StringSplitOptions.RemoveEmptyEntries))
+            {
+                WinningNumbers.Add(Int32.Parse(winningNumber));
+            }
+
+            // parse the scratchers
+            foreach (var scratchedNumber in scratchedNumbers.Split(' ', StringSplitOptions.RemoveEmptyEntries))
+            {
+                ScratchedNumbers.Add(Int32.Parse(scratchedNumber));
+            }
+        }
+
+        public int Points
+        {
+            get
+            {
+                int points = 0;
+                
+                foreach (var scratched in ScratchedNumbers)
+                {
+                    if (WinningNumbers.Contains(scratched))
+                    {
+                        if (points == 0) points = 1;
+                        else points *= 2;
+                    }
+                }
+
+                return points;
+            }
+        }
+
+        public List<int> MatchingNumbers
+        {
+            get 
+            { 
+                List<int> matches = new List<int>();
+
+                foreach (var scratched in ScratchedNumbers)
+                {
+                    if (WinningNumbers.Contains(scratched))
+                    {
+                        matches.Add(scratched);
+                    }
+                }
+
+                return matches;
+            }
+        }
+    }
+
+    public List<Card> Cards { get; private set; } = new List<Card>();
+
+    public Card GetCardNumber(int num)
+    {
+        if (Cards[num - 1].CardNumber != num) throw new InvalidDataException();
+
+        return Cards[num - 1];
+    }
+
+    public Day04Input(string fileName)
+        : base(fileName)
+    { 
+        foreach (var line in Lines)
+        {
+            Cards.Add(new Card(line));
+        }
+    }
+}