Completed day 15

AdvendOfCode.Runner/Program.cs

@@ -4,12 +4,12 @@ using AdventOfCode.Core;
 
 InputReader inputReader = new()
 {
-    IsDebug = true
+    //IsDebug = true
 };
 
 //inputReader.SetInputByChallange(3);
 
-IChallange challange = new Day14(inputReader);
+IChallange challange = new Day15(inputReader);
 
 Console.WriteLine($"Part 1: {await challange.GetSolutionPart1()}");
 

AdventOfCode.Solutions/2023/Day 15/Day15.cs

@@ -1,4 +1,5 @@
 using AdventOfCode.Core;
+using System.Text;
 
 namespace AdventOfCode.Solutions._2023
 {
@@ -8,12 +9,91 @@ namespace AdventOfCode.Solutions._2023
 
         public async Task<string> GetSolutionPart1()
         {
-            return string.Empty;
+            string[] data = (await _inputReader.ReadAsString()).Split(',', StringSplitOptions.RemoveEmptyEntries);
+            int stringTotal = 0;
+            foreach (string s in data)
+            {
+                stringTotal += GetHash(s);
+            }
+            return stringTotal.ToString();
         }
 
         public async Task<string> GetSolutionPart2()
         {
-            return string.Empty;
+            string[] data = (await _inputReader.ReadAsString()).Split(',', StringSplitOptions.RemoveEmptyEntries);
+            Dictionary<int, List<(string Label, int FocusLength)>> boxes = [];
+            int stringTotal = 0;
+            foreach (string s in data)
+            {
+                if (s.EndsWith('-'))
+                {
+                    string label = s[..^1];
+                    // remove
+                    int box = GetHash(label);
+                    if (boxes.TryGetValue(box, out var lensBox))
+                    {
+                        var currentLens = lensBox.FirstOrDefault(l => l.Label == label);
+                        if (!string.IsNullOrEmpty(currentLens.Label))
+                        {
+                            lensBox.Remove(currentLens);
+                        }
+                    }
+
+                    continue;
+                }
+
+                if (char.IsDigit(s[^1]))
+                {
+                    string label = s[..^2];
+                    int box = GetHash(label);
+                    int newFocal = int.Parse($"{s[^1]}");
+                    if (boxes.TryGetValue(box, out var lensBox))
+                    {
+                        var newLens = (label, newFocal);
+                        var currentLens = lensBox.FirstOrDefault(l => l.Label == label);
+                        if (!string.IsNullOrEmpty(currentLens.Label))
+                        {
+                            int index = lensBox.IndexOf(currentLens);
+                            lensBox[index] = newLens;
+                        }
+                        else
+                        {
+                            lensBox.Add(newLens);
+                        }
+                    }
+                    else
+                    {
+                        boxes.Add(box, [(label, newFocal)]);
+                    }
+                }
+            }
+
+            int total = 0;
+
+            //return boxes.Select(kvp => kvp.Key + 1 * GetBoxValue(kvp.Value)).Sum().ToString();
+
+            foreach(var box in boxes)
+            {
+                total += GetBoxValue(box.Key + 1, box.Value);
+            }
+
+            return total.ToString();
+        }
+
+        private static int GetBoxValue(int boxId, List<(string Label, int FocusLength)> box) => box.Select((kvp, index) => boxId * (index + 1) * kvp.FocusLength).Sum();
+
+        private static int GetBoxValue(Dictionary<string, int> box) => box.Select((kvp, index) => (index + 1) * kvp.Value).Sum();
+
+        private static int GetHash(string s)
+        {
+            int segementTotal = 0;
+            foreach (byte value in Encoding.ASCII.GetBytes(s))
+            {
+                segementTotal += value;
+                segementTotal *= 17;
+                segementTotal %= 256;
+            }
+            return segementTotal;
         }
     }
 }