quest 01 complete

everybody-codes/2025/EveryBodyCodes2025/EveryBodyCodes2025/EveryBodyCodes2025.fsproj

@@ -6,6 +6,21 @@
     </PropertyGroup>
 
     <ItemGroup>
+
+        <Content Include="Inputs\Quest01\Q01_P01.txt">
+          <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+        </Content>
+
+        <Content Include="Inputs\Quest01\Q01_P02.txt">
+          <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+        </Content>
+
+        <Content Include="Inputs\Quest01\Q01_P03.txt">
+          <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+        </Content>
+
+        <Compile Include="Helpers.fs" />
+        <Compile Include="Quest01.fs" />
         <Compile Include="Program.fs"/>
     </ItemGroup>
 

everybody-codes/2025/EveryBodyCodes2025/EveryBodyCodes2025/Helpers.fs

@@ -0,0 +1,18 @@
+module EveryBodyCodes2025.Helpers
+
+let foldUntilNone folder (state: 's) (source: 'a seq) : 's option =
+    use e = source.GetEnumerator()
+    let rec loop acc =
+        if e.MoveNext() then
+            match folder acc e.Current with
+            | Some s -> loop s
+            | None   -> Some acc   // last good state
+        else Some acc            // finished entire sequence
+    loop state
+
+let arraySwap idx0 idx1 (array: 'a array) =
+    let a = array[idx0]
+    let b = array[idx1]
+    array[idx0] <- b
+    array[idx1] <- a
+    array

everybody-codes/2025/EveryBodyCodes2025/EveryBodyCodes2025/Inputs/Quest01/Q01_P01.txt

@@ -0,0 +1,3 @@
+Krynnfal,Felnnyn,Norakmarn,Glynngnaris,Zorasis,Ulmarsarix,Rynquin,Wyntor,Harnmarn,Selkvel
+
+L6,R8,L7,R1,L2,R7,L1,R6,L5,R2,L7

everybody-codes/2025/EveryBodyCodes2025/EveryBodyCodes2025/Inputs/Quest01/Q01_P02.txt

@@ -0,0 +1,3 @@
+Ascalthar,Skarkael,Vyrbel,Havisis,Tarlzral,Paltheldrith,Hazthel,Hazwyris,Jarzyth,Mornxal,Vaelacris,Xardaros,Lirzyph,Sylacris,Nexor,Vorndra,Cyndhynd,Ralkyris,Cragkael,Galoryn
+
+L7,R12,L8,R12,L9,R18,L16,R13,L9,R12,L5,R11,L5,R14,L5,R18,L5,R15,L5,R17,L5,R18,L16,R12,L14,R7,L11,R9,L12

everybody-codes/2025/EveryBodyCodes2025/EveryBodyCodes2025/Inputs/Quest01/Q01_P03.txt

@@ -0,0 +1,3 @@
+Xarsar,Elvareldrin,Zraalcyth,Vyrlfeth,Palthonar,Maralor,Qalirin,Dalnyn,Havryn,Maralxal,Ulthyn,Ascalxeth,Thymfyr,Varinralis,Rythangarath,Ulkkynar,Lazlon,Grimulrix,Draithvash,Voraxmir,Vyrlxal,Elvarmal,Maralsyx,Wyrvash,Vornketh,Torendris,Thalcoryx,Paldeth,Vyrlcion,Tazroth
+
+L25,R49,L14,R13,L11,R12,L43,R45,L38,R34,L34,R44,L44,R35,L35,R30,L38,R37,L49,R48,L5,R39,L5,R27,L5,R14,L5,R32,L5,R46,L5,R9,L5,R24,L5,R43,L5,R21,L5,R22,L15,R49,L27,R41,L18,R31,L26,R16,L10,R40,L19,R6,L20,R24,L40,R44,L5,R47,L35

everybody-codes/2025/EveryBodyCodes2025/EveryBodyCodes2025/Program.fs

@@ -1,2 +1,13 @@
 // For more information see https://aka.ms/fsharp-console-apps
-printfn "Hello from F#"
+open EveryBodyCodes2025
+
+[<EntryPoint>]
+let main argv =
+
+    try
+        printfn $"{Quest01.part1()}"
+        printfn $"{Quest01.part2()}"
+        printfn $"{Quest01.part3()}"
+    with exn ->
+        printfn $"{exn}"
+    0

everybody-codes/2025/EveryBodyCodes2025/EveryBodyCodes2025/Quest01.fs

@@ -0,0 +1,81 @@
+module EveryBodyCodes2025.Quest01
+
+open System
+open System.IO
+open EveryBodyCodes2025.Helpers
+
+type Direction = Left | Right
+type Instruction = { Direction: Direction; Distance: int }
+let parseInstruction (segment:string) =
+    let direction = if segment[0] = 'L' then Left else Right
+    let distance = Int32.Parse(segment.AsSpan().Slice(1)) 
+    { Direction = direction; Distance = distance }
+    
+let inline normalize (array: 'a array) idx =
+    if idx >= 0 then idx % array.Length else array.Length - (-idx % array.Length)
+    
+let inline nextIndex instruction idx =
+    match instruction.Direction with
+    | Left -> idx - instruction.Distance
+    | Right -> idx + instruction.Distance
+    
+let readFile file =
+    File.ReadAllLines(file)
+    |> fun lines ->
+        let names = lines.[0] |> _.Split(",", StringSplitOptions.RemoveEmptyEntries ||| StringSplitOptions.TrimEntries)
+        let instructions =
+            lines[2]
+            |> _.Split(",", StringSplitOptions.RemoveEmptyEntries ||| StringSplitOptions.TrimEntries)
+            |> Array.map parseInstruction
+        (names, instructions)
+
+let part1File file : string =
+        readFile file
+        |> fun (names, instructions) ->
+                instructions
+                |> Seq.fold (fun (idx, _) instruction  ->
+                        let next = nextIndex instruction idx |> fun v -> Math.Clamp(v, 0, names.Length - 1)
+
+                        match Array.tryItem next names with
+                        | Some n -> next, n
+                        | None -> failwith "off array"
+                    ) (0, "")
+        |> snd
+        
+let part1 () = part1File "Inputs/Quest01/Q01_P01.txt"
+
+let part2File file =
+    readFile file
+    |> fun (names, instructions) ->
+        instructions
+        |> Seq.fold (fun (idx, _) instruction ->
+             let next =  nextIndex instruction idx |> normalize names
+             match Array.tryItem next names with
+                        | Some n -> next, n
+                        | None -> failwith "off array"
+                    ) (0, "")
+        |> snd
+
+let part2() = part2File "Inputs/Quest01/Q01_P02.txt"
+
+let part3File file =
+    readFile file
+    |> fun (names, instructions) ->
+        // need to preserve a reference to an array that can be mutated
+        let mutable nameArray = names
+        instructions
+        |> Seq.fold (fun _ instruction ->
+            // for this challenge the index doesn't matter
+            let next = match instruction.Direction with
+                        | Left -> names.Length - instruction.Distance
+                        | Right -> instruction.Distance
+                        |> normalize names
+            match Array.tryItem next nameArray with
+                        | Some n ->
+                            nameArray <- arraySwap 0 next names
+                            0, n
+                        | None -> failwith "off array"
+            ) (0, "")
+        |> snd
+
+let part3() = part3File  "Inputs/Quest01/Q01_P03.txt"