Imports System
Public Class Program
Public Shared Sub Main()
Dim s As String = "c c++, java, python, c# vb"
Dim comma As String = ","
Dim index As Integer = s.LastIndexOf(comma)
s = If((index < 0), s, s.Remove(index, comma.Length))
Console.Write(s)
End Sub
End Class
' run:
'
' c c++, java, python c# vb
'