Resolved Issue #3972

program/program/convert-string-to-alternatingcase/ConvertStringToAlternatingcase.fs

@@ -0,0 +1,21 @@
+open System
+
+let alternatingCase (input: string) =
+    let convert (c: char) (isUpper: bool) =
+        match Char.IsLetter c with
+        | true -> if isUpper then Char.ToUpper c else Char.ToLower c
+        | false -> c
+
+    let rec loop (str: string) (index: int) (isUpper: bool) =
+        if index < str.Length then
+            let updatedChar = convert str.[index] isUpper
+            let nextIsUpper = if Char.IsLetter str.[index] then not isUpper else isUpper
+            updatedChar.ToString() + loop str (index + 1) nextIsUpper
+        else
+            ""
+
+    loop input 0 false  // Start with lowercase for the first character
+
+// Example usage
+let result = alternatingCase "hello world"
+printfn "%s" result