public class Test
public Shared Sub Main
#If UseFastAlgorithm Then
Console.WriteLine("Fast")
#Else
Console.WriteLine("Slow")
#End If
#Const UseFastAlgorithm = True
#If UseFastAlgorithm Then
Console.WriteLine("Fast")
#Else
Console.WriteLine("Slow")
#End If
End Sub
End class
Slow
Fast