Day 15 part 1

Day15/AsciiHash.cs

@@ -0,0 +1,18 @@
+using System.Text;
+
+namespace Day15;
+
+public static class AsciiHash
+{
+    public static byte Hash(string input)
+    {
+        byte result = 0;
+        foreach (var b in Encoding.ASCII.GetBytes(input))
+        {
+            result += b;
+            result = (byte)((result * 17) % 256);
+        }
+
+        return result;
+    }
+}

Day15/InitializationStep.cs

@@ -0,0 +1,9 @@
+namespace Day15;
+
+public record InitializationStep(string Instruction)
+{
+    public byte GetHash()
+    {
+        return AsciiHash.Hash(Instruction);
+    }
+}

Day15/Parser.cs

@@ -7,13 +7,12 @@ public partial class Parser
     [GeneratedRegex(@".*")]
     private partial Regex LineMatch();
     
-    public void Parse(string inputFile)
+    public IEnumerable<InitializationStep> Parse(string inputFile)
     {
-        using var reader = File.OpenText(inputFile);
-        
-        while (!reader.EndOfStream)
+        var text = File.ReadAllText(inputFile);
+        foreach (var step in text.Split(',', StringSplitOptions.TrimEntries | StringSplitOptions.RemoveEmptyEntries))
         {
-            var line = reader.ReadLine()!;
+            yield return new InitializationStep(step);
         }
     }
 }

Day15/Program.cs

@@ -16,5 +16,17 @@ if (args.Length < 1)
 
 var inputFile = args[0];
 var parser = new Parser();
+var steps = parser.Parse(inputFile);
+
+var sum = 0;
+foreach (var s in steps)
+{
+    var hash = s.GetHash();
+    Console.WriteLine(hash);
+    sum += hash;
+}
+
+Console.WriteLine();
+Console.WriteLine($"Total: {sum}");
 
 return 0;

Day15/inputs/sample1.txt

@@ -0,0 +1 @@
+rn=1,cm-,qp=3,cm=2,qp-,pc=4,ot=9,ab=5,pc-,pc=6,ot=7