Stop going insane

AdventOfCode2023.FSharp/AdventOfCode2023.FSharp.Lib/ResizeArray.fs

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+namespace AdventOfCode2023.ResizeArray
+
+open System
+
+type ResizeArray<'T> =
+    private
+        {
+            mutable Array: 'T array
+            mutable Length: int
+        }
+
+    member this.Count = this.Length
+    member this.Clear () = this.Length <- 0
+    member this.Add (t : 'T) =
+        if this.Length < this.Array.Length then
+            this.Array.[this.Length] <- t
+        else
+            let newLength = this.Length * 2
+            let newArray = Array.zeroCreate<'T> newLength
+            Array.blit this.Array 0 newArray 0 this.Length
+            newArray.[this.Length] <- t
+            this.Array <- newArray
+        this.Length <- this.Length + 1
+    member this.Item
+        with get (i : int) = this.Array.[i]
+        and set (i : int) (t : 'T) = this.Array.[i] <- t
+
+    member this.Sort () =
+        Span(this.Array).Slice(0, this.Count).Sort ()
+
+[<RequireQualifiedAccess>]
+module ResizeArray =
+    let create<'T> (capacity : int) = { Array = Array.zeroCreate<'T> capacity; Length = 0 }