Finish day 5

2 files changed, 89 insertions, 0 deletions

diff --git a/aoc-2022-dotnet/Day05/Day05.fsproj b/aoc-2022-dotnet/Day05/Day05.fsproj
new file mode 100644
index 0000000..44c3fba
--- /dev/null
+++ b/aoc-2022-dotnet/Day05/Day05.fsproj
@@ -0,0 +1,22 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Content Include="test.txt">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+    <Content Include="input.txt">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+    <Compile Include="Program.fs" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="FParsec" Version="1.1.1" />
+  </ItemGroup>
+
+</Project>
diff --git a/aoc-2022-dotnet/Day05/Program.fs b/aoc-2022-dotnet/Day05/Program.fs
new file mode 100644
index 0000000..e15f53d
--- /dev/null
+++ b/aoc-2022-dotnet/Day05/Program.fs
@@ -0,0 +1,67 @@
+open System
+open System.IO
+open FParsec
+
+type Move =
+    | Move of int * int * int
+
+    static member parse str =
+        let dec n = n - 1
+        let pPart str = pstring str >>. pint32
+        let pMove = tuple3 (pPart "move ") (pPart " from " |>> dec) (pPart " to " |>> dec)
+
+        match run pMove str with
+        | Success (result, _, _) -> Move result
+        | _ -> failwith "Invalid move format!"
+
+    static member execute order stacks (Move (n, fi, ti)) =
+        List.mapi
+            (fun i x ->
+                if i = fi then
+                    List.item fi stacks |> List.skip n
+                elif i = ti then
+                    (List.item fi stacks |> List.take n |> order)
+                    @ List.item ti stacks
+                else
+                    x)
+            stacks
+
+let parseStacks str =
+    let pFullCrate = pchar '[' >>. anyChar .>> pchar ']' |>> Some
+    let pEmptyCrate = pstring "   " >>% None
+    let pCrate = pFullCrate <|> pEmptyCrate
+    let pCrateLine = sepBy pCrate (pchar ' ') .>> skipNewline
+    let pHeader = many pCrateLine
+
+    let parsed =
+        match run pHeader str with
+        | Success (result, _, _) -> result
+        | _ -> failwith "Invalid header format!"
+
+    parsed
+    |> List.transpose
+    |> List.map (List.choose id)
+
+let solve order input =
+    let headerList =
+        input
+        |> Seq.takeWhile (not << String.IsNullOrEmpty)
+        |> Seq.toList
+
+    let stacks = parseStacks <| String.Join("\n", headerList)
+
+    String.Concat(
+        input
+        |> Seq.skip (headerList.Length + 1)
+        |> Seq.map Move.parse
+        |> Seq.fold (Move.execute order) stacks
+        |> List.map List.head
+    )
+
+let test = File.ReadLines "test.txt"
+assert (solve List.rev test = "CMZ")
+assert (solve id test = "MCD")
+
+let input = File.ReadLines "input.txt"
+printfn "%s" <| solve List.rev input
+printfn "%s" <| solve id input