Day 9

.woodpecker/.build.yml

@@ -3,17 +3,6 @@ steps:
     image: nixos/nix
     commands:
       - echo 'experimental-features = flakes nix-command' >> /etc/nix/nix.conf
-
-      - "nix develop --command dotnet publish AdventOfCode2023.FSharp/AdventOfCode2023.FSharp/AdventOfCode2023.FSharp.fsproj --configuration Release -p:PublishAot=true || echo 'First publish failed'"
-      - "nix develop --command sh -c 'patchelf --set-interpreter $LINKER_PATH /tmp/dotnet-home/.nuget/packages/runtime.linux-x64.microsoft.dotnet.ilcompiler/8.0.0/tools/ilc'"
-      - "ls -al /tmp/dotnet-home/.nuget/packages/runtime.linux-x64.microsoft.dotnet.ilcompiler/8.0.0/tools/ilc"
-      - "chmod a+x /tmp/dotnet-home/.nuget/packages/runtime.linux-x64.microsoft.dotnet.ilcompiler/8.0.0/tools/ilc"
-      - "ls -al /tmp/dotnet-home/.nuget/packages/runtime.linux-x64.microsoft.dotnet.ilcompiler/8.0.0/tools/ilc"
-      - "whoami"
-      - "cp -r AdventOfCode2023.FSharp/AdventOfCode2023.FSharp/obj /tmp/obj"
-      - "nix develop --command sh -c 'ls -la $LINKER_PATH'"
-      - "nix develop --command sh -c 'strace /tmp/dotnet-home/.nuget/packages/runtime.linux-x64.microsoft.dotnet.ilcompiler/8.0.0/tools/ilc /tmp/obj/Release/net8.0/linux-x64/native/AdventOfCode2023.FSharp.ilc.rsp'"
-      - "nix develop --command dotnet publish AdventOfCode2023.FSharp/AdventOfCode2023.FSharp/AdventOfCode2023.FSharp.fsproj --configuration Release -p:PublishAot=true"
       # Lint
       - "nix flake check"
       # Test

AdventOfCode2023.FSharp/AdventOfCode2023.FSharp.Lib/AdventOfCode2023.FSharp.Lib.fsproj

@@ -1,23 +1,25 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-    <PropertyGroup>
-        <TargetFramework>net8.0</TargetFramework>
-        <GenerateDocumentationFile>true</GenerateDocumentationFile>
-    </PropertyGroup>
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
+  </PropertyGroup>
 
-    <ItemGroup>
-        <Compile Include="Arr2D.fs" />
-        <Compile Include="ResizeArray.fs" />
-        <Compile Include="EfficientString.fs" />
-        <Compile Include="Arithmetic.fs" />
-        <Compile Include="Day1.fs" />
-        <Compile Include="Day2.fs" />
-        <Compile Include="Day3.fs" />
-        <Compile Include="Day4.fs" />
-        <Compile Include="Day5.fs" />
-        <Compile Include="Day6.fs" />
-        <Compile Include="Day7.fs" />
-        <Compile Include="Day8.fs" />
-    </ItemGroup>
+  <ItemGroup>
+    <Compile Include="Arr2D.fs"/>
+    <Compile Include="ResizeArray.fs"/>
+    <Compile Include="EfficientString.fs"/>
+    <Compile Include="Arithmetic.fs"/>
+    <Compile Include="Rational.fs"/>
+    <Compile Include="Day1.fs"/>
+    <Compile Include="Day2.fs"/>
+    <Compile Include="Day3.fs"/>
+    <Compile Include="Day4.fs"/>
+    <Compile Include="Day5.fs"/>
+    <Compile Include="Day6.fs"/>
+    <Compile Include="Day7.fs"/>
+    <Compile Include="Day8.fs"/>
+    <Compile Include="Day9.fs"/>
+  </ItemGroup>
 
 </Project>

AdventOfCode2023.FSharp/AdventOfCode2023.FSharp.Lib/Day9.fs

@@ -0,0 +1,55 @@
+namespace AdventOfCode2023
+
+open System
+
+[<RequireQualifiedAccess>]
+module Day9 =
+
+    let extrapolate (isStart : bool) (arr : ResizeArray<int64>) =
+        let mutable answer = 0L
+        let pos = if isStart then -1L else int64 arr.Count
+
+        for i = 0 to arr.Count - 1 do
+            let mutable product = Rational.ofInt arr.[i]
+
+            for j = 0 to arr.Count - 1 do
+                if j <> i then
+                    product <- product * Rational.make (pos - int64 j) (int64 i - int64 j)
+
+            answer <- answer + Rational.assertIntegral product
+
+        answer
+
+    let part1 (s : string) =
+        use s = StringSplitEnumerator.make '\n' s
+        let mutable answer = 0L
+        let arr = ResizeArray ()
+
+        for line in s do
+            arr.Clear ()
+            use line = StringSplitEnumerator.make' ' ' line
+
+            for number in line do
+                let number = Int64.Parse number
+                arr.Add number
+
+            answer <- answer + extrapolate false arr
+
+        answer
+
+    let part2 (s : string) =
+        use s = StringSplitEnumerator.make '\n' s
+        let mutable answer = 0L
+        let arr = ResizeArray ()
+
+        for line in s do
+            arr.Clear ()
+            use line = StringSplitEnumerator.make' ' ' line
+
+            for number in line do
+                let number = Int64.Parse number
+                arr.Add number
+
+            answer <- answer + extrapolate true arr
+
+        answer

AdventOfCode2023.FSharp/AdventOfCode2023.FSharp.Lib/EfficientString.fs

@@ -1,7 +1,6 @@
 namespace AdventOfCode2023
 
 open System
-open System.Globalization
 open System.Runtime.CompilerServices
 
 type EfficientString = System.ReadOnlySpan<char>

AdventOfCode2023.FSharp/AdventOfCode2023.FSharp.Lib/Rational.fs

@@ -0,0 +1,82 @@
+namespace AdventOfCode2023
+
+[<Struct>]
+type Rational<'a
+    when 'a : (static member (+) : 'a * 'a -> 'a)
+    and 'a : (static member (*) : 'a * 'a -> 'a)
+    and 'a : (static member (/) : 'a * 'a -> 'a)
+    and 'a : (static member (-) : 'a * 'a -> 'a)
+    and 'a : (static member Zero : 'a)
+    and 'a : (static member One : 'a)
+    and 'a : comparison> =
+    {
+        Numerator : 'a
+        Denominator : 'a
+    }
+
+    static member inline (+) (a : Rational<'a>, b : Rational<'a>) =
+        let numerator = a.Numerator * b.Denominator + b.Numerator * a.Denominator
+        let denominator = a.Denominator * b.Denominator
+        let hcf = (Arithmetic.euclideanAlgorithm numerator denominator).Hcf
+
+        {
+            Numerator = numerator / hcf
+            Denominator = denominator / hcf
+        }
+
+    static member inline (*) (a : Rational<'a>, b : Rational<'a>) =
+        let numerator = a.Numerator * b.Numerator
+        let denominator = a.Denominator * b.Denominator
+        let hcf = (Arithmetic.euclideanAlgorithm numerator denominator).Hcf
+
+        {
+            Numerator = numerator / hcf
+            Denominator = denominator / hcf
+        }
+
+[<RequireQualifiedAccess>]
+module Rational =
+    let inline ofInt< ^a
+        when 'a : (static member (+) : 'a * 'a -> 'a)
+        and 'a : (static member (*) : 'a * 'a -> 'a)
+        and 'a : (static member (/) : 'a * 'a -> 'a)
+        and 'a : (static member (-) : 'a * 'a -> 'a)
+        and 'a : (static member Zero : 'a)
+        and 'a : (static member One : 'a)
+        and 'a : comparison>
+        (a : 'a)
+        =
+        {
+            Numerator = a
+            Denominator = LanguagePrimitives.GenericOne
+        }
+
+    let inline make< ^a
+        when 'a : (static member (+) : 'a * 'a -> 'a)
+        and 'a : (static member (*) : 'a * 'a -> 'a)
+        and 'a : (static member (/) : 'a * 'a -> 'a)
+        and 'a : (static member (-) : 'a * 'a -> 'a)
+        and 'a : (static member Zero : 'a)
+        and 'a : (static member One : 'a)
+        and 'a : comparison>
+        (numerator : 'a)
+        (denominator : 'a)
+        =
+        let hcf = (Arithmetic.euclideanAlgorithm numerator denominator).Hcf
+
+        {
+            Numerator = numerator / hcf
+            Denominator = denominator / hcf
+        }
+
+    let inline assertIntegral< ^a
+        when 'a : (static member (+) : 'a * 'a -> 'a)
+        and 'a : (static member (*) : 'a * 'a -> 'a)
+        and 'a : (static member (/) : 'a * 'a -> 'a)
+        and 'a : (static member (-) : 'a * 'a -> 'a)
+        and 'a : (static member Zero : 'a)
+        and 'a : (static member One : 'a)
+        and 'a : comparison>
+        (r : Rational<'a>)
+        =
+        r.Numerator

AdventOfCode2023.FSharp/AdventOfCode2023.FSharp/AdventOfCode2023.FSharp.fsproj

@@ -1,28 +1,28 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-    <PropertyGroup>
-        <OutputType>Exe</OutputType>
-        <TargetFramework>net8.0</TargetFramework>
-        <PublishAot>true</PublishAot>
-        <InvariantGlobalization>true</InvariantGlobalization>
-        <UseSystemResourceKeys>true</UseSystemResourceKeys>
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <PublishAot>true</PublishAot>
+    <InvariantGlobalization>true</InvariantGlobalization>
+    <UseSystemResourceKeys>true</UseSystemResourceKeys>
 
-        <IlcOptimizationPreference>Speed</IlcOptimizationPreference>
-        <IlcGenerateStackTraceData>false</IlcGenerateStackTraceData>
+    <IlcOptimizationPreference>Speed</IlcOptimizationPreference>
+    <IlcGenerateStackTraceData>false</IlcGenerateStackTraceData>
 
-        <DebuggerSupport>false</DebuggerSupport>
-        <EnableUnsafeBinaryFormatterSerialization>false</EnableUnsafeBinaryFormatterSerialization>
-        <EventSourceSupport>false</EventSourceSupport>
-        <HttpActivityPropagationSupport>false</HttpActivityPropagationSupport>
-        <MetadataUpdaterSupport>false</MetadataUpdaterSupport>
-    </PropertyGroup>
+    <DebuggerSupport>false</DebuggerSupport>
+    <EnableUnsafeBinaryFormatterSerialization>false</EnableUnsafeBinaryFormatterSerialization>
+    <EventSourceSupport>false</EventSourceSupport>
+    <HttpActivityPropagationSupport>false</HttpActivityPropagationSupport>
+    <MetadataUpdaterSupport>false</MetadataUpdaterSupport>
+  </PropertyGroup>
 
-    <ItemGroup>
-        <Compile Include="Program.fs"/>
-    </ItemGroup>
+  <ItemGroup>
+    <Compile Include="Program.fs"/>
+  </ItemGroup>
 
-    <ItemGroup>
-      <ProjectReference Include="..\AdventOfCode2023.FSharp.Lib\AdventOfCode2023.FSharp.Lib.fsproj" />
-    </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\AdventOfCode2023.FSharp.Lib\AdventOfCode2023.FSharp.Lib.fsproj"/>
+  </ItemGroup>
 
 </Project>

AdventOfCode2023.FSharp/AdventOfCode2023.FSharp/Program.fs

@@ -179,6 +179,22 @@ module Program =
             Console.WriteLine (part2.ToString ())
             Console.Error.WriteLine ((1_000.0 * float sw.ElapsedTicks / float Stopwatch.Frequency).ToString () + "ms")
 
+        Console.WriteLine "=====Day 9====="
+
+        do
+            let input = Path.Combine (dir.FullName, "day9.txt") |> File.ReadAllText
+
+            sw.Restart ()
+            let part1 = Day9.part1 input
+            sw.Stop ()
+            Console.WriteLine (part1.ToString ())
+            Console.Error.WriteLine ((1_000.0 * float sw.ElapsedTicks / float Stopwatch.Frequency).ToString () + "ms")
+            sw.Restart ()
+            let part2 = Day9.part2 input
+            sw.Stop ()
+            Console.WriteLine (part2.ToString ())
+            Console.Error.WriteLine ((1_000.0 * float sw.ElapsedTicks / float Stopwatch.Frequency).ToString () + "ms")
+
         endToEnd.Stop ()
 
         Console.Error.WriteLine (

AdventOfCode2023.FSharp/Test/Test.fsproj

@@ -1,44 +1,46 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-    <PropertyGroup>
-        <TargetFramework>net8.0</TargetFramework>
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
 
-        <IsPackable>false</IsPackable>
-        <IsTestProject>true</IsTestProject>
-    </PropertyGroup>
+    <IsPackable>false</IsPackable>
+    <IsTestProject>true</IsTestProject>
+  </PropertyGroup>
 
-    <ItemGroup>
-        <Compile Include="Util.fs" />
-        <Compile Include="TestDay1.fs" />
-        <Compile Include="TestDay2.fs" />
-        <Compile Include="TestDay3.fs" />
-        <Compile Include="TestDay4.fs" />
-        <Compile Include="TestDay5.fs" />
-        <Compile Include="TestDay6.fs" />
-        <Compile Include="TestDay7.fs" />
-        <Compile Include="TestDay8.fs" />
-        <EmbeddedResource Include="samples\day1.txt" />
-        <EmbeddedResource Include="samples\day1part1.txt" />
-        <EmbeddedResource Include="samples\day2.txt" />
-        <EmbeddedResource Include="samples\day3.txt" />
-        <EmbeddedResource Include="samples\day4.txt" />
-        <EmbeddedResource Include="samples\day5.txt" />
-        <EmbeddedResource Include="samples\day6.txt" />
-        <EmbeddedResource Include="samples\day7.txt" />
-        <EmbeddedResource Include="samples\day8part1.txt" />
-        <EmbeddedResource Include="samples\day8.txt" />
-    </ItemGroup>
+  <ItemGroup>
+    <Compile Include="Util.fs"/>
+    <Compile Include="TestDay1.fs"/>
+    <Compile Include="TestDay2.fs"/>
+    <Compile Include="TestDay3.fs"/>
+    <Compile Include="TestDay4.fs"/>
+    <Compile Include="TestDay5.fs"/>
+    <Compile Include="TestDay6.fs"/>
+    <Compile Include="TestDay7.fs"/>
+    <Compile Include="TestDay8.fs"/>
+    <Compile Include="TestDay9.fs"/>
+    <EmbeddedResource Include="samples\day1.txt"/>
+    <EmbeddedResource Include="samples\day1part1.txt"/>
+    <EmbeddedResource Include="samples\day2.txt"/>
+    <EmbeddedResource Include="samples\day3.txt"/>
+    <EmbeddedResource Include="samples\day4.txt"/>
+    <EmbeddedResource Include="samples\day5.txt"/>
+    <EmbeddedResource Include="samples\day6.txt"/>
+    <EmbeddedResource Include="samples\day7.txt"/>
+    <EmbeddedResource Include="samples\day8part1.txt"/>
+    <EmbeddedResource Include="samples\day8.txt"/>
+    <EmbeddedResource Include="samples\day9.txt"/>
+  </ItemGroup>
 
-    <ItemGroup>
-        <PackageReference Include="FsUnit" Version="5.6.1" />
-        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.6.0"/>
-        <PackageReference Include="NUnit3TestAdapter" Version="4.2.1"/>
-        <PackageReference Include="NUnit.Analyzers" Version="3.6.1"/>
-        <PackageReference Include="coverlet.collector" Version="6.0.0"/>
-    </ItemGroup>
+  <ItemGroup>
+    <PackageReference Include="FsUnit" Version="5.6.1"/>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.6.0"/>
+    <PackageReference Include="NUnit3TestAdapter" Version="4.2.1"/>
+    <PackageReference Include="NUnit.Analyzers" Version="3.6.1"/>
+    <PackageReference Include="coverlet.collector" Version="6.0.0"/>
+  </ItemGroup>
 
-    <ItemGroup>
-      <ProjectReference Include="..\AdventOfCode2023.FSharp.Lib\AdventOfCode2023.FSharp.Lib.fsproj" />
-    </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\AdventOfCode2023.FSharp.Lib\AdventOfCode2023.FSharp.Lib.fsproj"/>
+  </ItemGroup>
 
 </Project>

AdventOfCode2023.FSharp/Test/TestDay5.fs

@@ -1,6 +1,5 @@
 namespace AdventOfCode2023.Test
 
-open System
 open AdventOfCode2023
 open NUnit.Framework
 open FsUnitTyped

AdventOfCode2023.FSharp/Test/TestDay6.fs

@@ -1,6 +1,5 @@
 namespace AdventOfCode2023.Test
 
-open System
 open AdventOfCode2023
 open NUnit.Framework
 open FsUnitTyped

AdventOfCode2023.FSharp/Test/TestDay7.fs

@@ -1,6 +1,5 @@
 namespace AdventOfCode2023.Test
 
-open System
 open AdventOfCode2023
 open NUnit.Framework
 open FsUnitTyped

AdventOfCode2023.FSharp/Test/TestDay9.fs

@@ -0,0 +1,47 @@
+namespace AdventOfCode2023.Test
+
+open AdventOfCode2023
+open NUnit.Framework
+open FsUnitTyped
+open System.IO
+
+[<TestFixture>]
+module TestDay9 =
+
+    let sample = Assembly.getEmbeddedResource typeof<Dummy>.Assembly "day9.txt"
+
+    [<Test>]
+    let part1Sample () =
+        sample |> Day9.part1 |> shouldEqual 114L
+
+    [<Test>]
+    let part2Sample () =
+        Assembly.getEmbeddedResource typeof<Dummy>.Assembly "day9.txt"
+        |> Day9.part2
+        |> shouldEqual 2L
+
+    [<Test>]
+    let part1Actual () =
+        let s =
+            try
+                File.ReadAllText (Path.Combine (__SOURCE_DIRECTORY__, "../../inputs/day9.txt"))
+            with
+            | :? DirectoryNotFoundException
+            | :? FileNotFoundException ->
+                Assert.Inconclusive ()
+                failwith "unreachable"
+
+        Day9.part1 s |> shouldEqual 1898776583L
+
+    [<Test>]
+    let part2Actual () =
+        let s =
+            try
+                File.ReadAllText (Path.Combine (__SOURCE_DIRECTORY__, "../../inputs/day9.txt"))
+            with
+            | :? DirectoryNotFoundException
+            | :? FileNotFoundException ->
+                Assert.Inconclusive ()
+                failwith "unreachable"
+
+        Day9.part2 s |> shouldEqual 1100L

AdventOfCode2023.FSharp/Test/samples/day9.txt

@@ -0,0 +1,3 @@
+0 3 6 9 12 15
+1 3 6 10 15 21
+10 13 16 21 30 45

flake.lock

@@ -18,26 +18,6 @@
         "type": "github"
       }
     },
-    "nix-ld": {
-      "inputs": {
-        "nixpkgs": [
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1701153607,
-        "narHash": "sha256-h+odOVyiGmEERMECoFOj5P7FPiMR8IPRzroFA4sKivg=",
-        "owner": "Mic92",
-        "repo": "nix-ld",
-        "rev": "bf5aa84a713c31d95b4307e442e966d6c7fd7ae7",
-        "type": "github"
-      },
-      "original": {
-        "owner": "Mic92",
-        "repo": "nix-ld",
-        "type": "github"
-      }
-    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1701253981,
@@ -57,7 +37,6 @@
     "root": {
       "inputs": {
         "flake-utils": "flake-utils",
-        "nix-ld": "nix-ld",
         "nixpkgs": "nixpkgs"
       }
     },

flake.nix

@@ -3,17 +3,12 @@
   inputs = {
     flake-utils.url = "github:numtide/flake-utils";
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
-    nix-ld = {
-      url = "github:Mic92/nix-ld";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
   };
 
   outputs = {
     self,
     nixpkgs,
     flake-utils,
-    nix-ld,
   }:
     flake-utils.lib.eachDefaultSystem (
       system: let
@@ -30,14 +25,9 @@
               pkgs.darwin.apple_sdk.frameworks.GSS
             ]
             else [];
-        in let
-          deps = darwinDeps ++ [pkgs.zlib pkgs.zlib.dev pkgs.openssl pkgs.icu];
         in {
           devShells = {
             default = pkgs.mkShell {
-              HOME = "/tmp/dotnet-home";
-              NUGET_PACKAGES = "/tmp/dotnet-home/.nuget/packages";
-              LINKER_PATH = "${pkgs.stdenv.cc}/nix-support/dynamic-linker";
               buildInputs = with pkgs;
                 [
                   (with dotnetCorePackages;
@@ -46,7 +36,8 @@
                       dotnetPackages.Nuget
                     ])
                 ]
-                ++ [pkgs.alejandra pkgs.patchelf pkgs.strace];
+                ++ darwinDeps
+                ++ [pkgs.zlib pkgs.zlib.dev pkgs.openssl pkgs.icu pkgs.alejandra];
             };
           };
         }