Как избежать округления чисел в функции

Option Explicit
Sub v1()
Dim a As Double, s As Integer, i As Integer
Sheets("Лист1").Select
Range("a1:c5").Clear
For i = 1 To 5
  a = Val(InputBox("Введите a(" + Trim(Str(i)) + ")"))
  s = funs(a)
  Cells(i, 1) = a
  Cells(i, 3) = s
Next i
End Sub
 
Function funs(ByVal a As Double) As Double
Dim s As Integer, stra As String, i As Integer
stra = Str(a) ' здесь переменная а уже округлена
s = 0
stra = Left(stra, Len(stra) - InStr(stra, "."))
For i = 1 To Len(stra)
  s = s + Val(Mid(stra, i, 1))
Next i
funs = a
End Function

 a = Val(InputBox("Введите a(" + Trim(Str(i)) + ")"))

 a = Val(replace(InputBox("Введите a(" + Trim(Str(i)) + ")")),",",".")

Sub v1()
Dim a As Double, s , i As Integer
Sheets("Ëèñò1").Select
Range("a1:c5").Clear
For i = 1 To 5
  a = Val(Replace(InputBox("Ââåäèòå a(" + Trim(Str(i)) + ")"), ",", "."))
  s = funs(a)
  Cells(i, 1) = a
  Cells(i, 3) = s
Next i
End Sub
 
Function funs(ByVal a As Double) As String
Dim p%
funs = CStr(a)
p = InStr(1, funs, ",")
If p > 1 Then
funs = Left(funs, p - 2) & Mid(funs, p)
Else
funs = CStr(a \ 10)
End If
End Function

Dim a As Double, s As Double, i As Integer

Function funs(a As Double) As Double
funs = a - Fix(a) + Fix(a / 10)
End Function

Option Explicit
Sub v1()
Dim a As Double, s As String, i As Integer
Sheets("Лист1").Select
Range("a1:c20").Clear
For i = 1 To 5
  a = Val(InputBox("Введите a(" + Trim(Str(i)) + ")"))
  s = funs(a)
  Cells(i, 1) = a
  Cells(i, 3) = s
Next i
End Sub
 
Function funs(ByVal a As Double) As Double
Dim s As String, stra As String, stra2, i As Integer, count, TestString As String, subString As String, LeftString, RightString
stra = CStr(a)
count = InStr(stra, ",")
If count = 0 Then
    If Len(stra) < 2 Then
        TestString = 0
    Else
         count = (Len(stra) - 1)
         TestString = Left(stra, count)
    End If
Else
LeftString = Left(stra, (count))
RightString = Right(stra, (Len(stra) - count))
 If Len(LeftString) < 3 Then
        TestString = "0" + "," + RightString
    Else
        count = (Len(LeftString) - 2)
         LeftString = Left(LeftString, count)
          MsgBox (LeftString)
          subString = ","
         'TestString = LeftString + "," + RightString
         TestString = LeftString & subString & RightString
    End If
 
End If
 
funs = TestString
End Function