Dim out_HF_Accepted_Codes As String = “K51.90,C78.6”
Dim IcCodes As String = “K51.90,C78.6,K12.850”
’ Split the input strings into arrays
Dim out_HF_Accepted_Codes_Array As String() = out_HF_Accepted_Codes.Split(",“c)
Dim IcCodes_Array As String() = IcCodes.Split(”,"c)
’ Use LINQ to find the unique elements
Dim uniqueElements = IcCodes_Array.Except(out_HF_Accepted_Codes_Array)
’ Concatenate the unique elements into a string
Dim output As String = String.Join(“,”, uniqueElements)