Add day 1

AdventOfCode.csproj

@@ -2,9 +2,10 @@
 
     <PropertyGroup>
         <OutputType>Exe</OutputType>
-        <TargetFramework>net8.0</TargetFramework>
+        <TargetFramework>net9.0</TargetFramework>
         <ImplicitUsings>enable</ImplicitUsings>
         <Nullable>enable</Nullable>
+        <LangVersion>latest</LangVersion>
     </PropertyGroup>
 
     <ItemGroup>
@@ -13,8 +14,8 @@
     </ItemGroup>
 
     <ItemGroup>
-      <None Remove="Inputs\Day1.txt" />
-      <EmbeddedResource Include="Inputs\Day1.txt" />
+      <None Remove="Inputs\*" />
+      <EmbeddedResource Include="Inputs\*" />
     </ItemGroup>
 
 </Project>

Days/Day1.cs

@@ -5,96 +5,60 @@ namespace AdventOfCode.Days;
 public class Day1 : Day
 {
     public override int Number => 1;
-    public override string Name => "Trebuchet?!";
-
-    private static readonly (string, int)[] WrittenDigits =
-    [
-        ("one"  , 1),
-        ("two"  , 2),
-        ("three", 3),
-        ("four" , 4),
-        ("five" , 5),
-        ("six"  , 6),
-        ("seven", 7),
-        ("eight", 8),
-        ("nine" , 9)
-    ];
+    public override string Name => "Historian Hysteria";
 
     public override void RunPart1(bool display = true)
     {
-        var calibrationSum = 0;
+        List<int> leftNumbers = [];
+        List<int> rightNumbers = [];
 
         foreach (var line in Input.AsSpan().EnumerateLines())
         {
-            var firstDigitIndex = line.IndexOfAnyInRange('0', '9');
-            var lastDigitIndex = line.LastIndexOfAnyInRange('0', '9');
+            var separatorIndex = line.IndexOf(' ');
 
-            var firstDigit = line[firstDigitIndex] - '0';
-            var lastDigit = line[lastDigitIndex] - '0';
-
-            calibrationSum += firstDigit * 10 + lastDigit;
+            leftNumbers.Add(int.Parse(line[..separatorIndex]));
+            rightNumbers.Add(int.Parse(line[(separatorIndex + 1)..]));
         }
 
+        leftNumbers.Sort();
+        rightNumbers.Sort();
+
+        var totalDistance = leftNumbers.Zip(rightNumbers, (a, b) => Math.Abs(a - b)).Sum();
+
         if (display)
         {
-            AnsiConsole.MarkupLine($"[green]Sum of calibration values is: [yellow]{calibrationSum}[/][/]");
+            AnsiConsole.MarkupLine($"[green]Total distance is: [yellow]{totalDistance}[/][/]");
         }
     }
 
     public override void RunPart2(bool display = true)
     {
-        var calibrationSum = 0;
+        List<int> leftNumbers = [];
+        Dictionary<int, int> rightNumbersCount = [];
+        var similarityScore = 0;
 
         foreach (var line in Input.AsSpan().EnumerateLines())
         {
-            var minFirstDigitIndex = line.IndexOfAnyInRange('0', '9');
-            var maxLastDigitIndex = line.LastIndexOfAnyInRange('0', '9');
+            var separatorIndex = line.IndexOf(' ');
 
-            var firstDigitValue = 0;
-            if (minFirstDigitIndex == -1)
+            leftNumbers.Add(int.Parse(line[..separatorIndex]));
+
+            var rightNumber = int.Parse(line[(separatorIndex + 1)..]);
+
+            if (!rightNumbersCount.TryAdd(rightNumber, 1))
             {
-                minFirstDigitIndex = int.MaxValue;
-            }
-            else
-            {
-                firstDigitValue = line[minFirstDigitIndex] - '0';
+                rightNumbersCount[rightNumber]++;
             }
+        }
 
-            var lastDigitValue = 0;
-            if (maxLastDigitIndex == -1)
-            {
-                maxLastDigitIndex = int.MinValue;
-            }
-            else
-            {
-                lastDigitValue = line[maxLastDigitIndex] - '0';
-            }
-
-            foreach (var (writtenDigit, value) in WrittenDigits)
-            {
-                var firstWrittenDigitIndex = line.IndexOf(writtenDigit);
-
-                if (firstWrittenDigitIndex != -1 && firstWrittenDigitIndex < minFirstDigitIndex)
-                {
-                    minFirstDigitIndex = firstWrittenDigitIndex;
-                    firstDigitValue = value;
-                }
-
-                var lastWrittenDigitIndex = line.LastIndexOf(writtenDigit);
-
-                if (lastWrittenDigitIndex != -1 && lastWrittenDigitIndex > maxLastDigitIndex)
-                {
-                    maxLastDigitIndex = lastWrittenDigitIndex;
-                    lastDigitValue = value;
-                }
-            }
-
-            calibrationSum += 10 * firstDigitValue + lastDigitValue;
+        foreach (var leftNumber in leftNumbers)
+        {
+            similarityScore += leftNumber * rightNumbersCount.GetValueOrDefault(leftNumber);
         }
 
         if (display)
         {
-            AnsiConsole.MarkupLine($"[green]Sum of calibration values is: [yellow]{calibrationSum}[/][/]");
+            AnsiConsole.MarkupLine($"[green]Similarity score is: [yellow]{similarityScore}[/][/]");
         }
     }
 }