Imports System
Public Class myProgram
Private Shared Function get_last_N_bits(ByVal number As Integer, ByVal N As Integer) As Integer
Dim mask As Integer = (1 << N) - 1
Return number AND mask
End Function
Public Shared Sub Main()
Dim number As Integer = 441 ' 00000001101-11001
Dim N As Integer = 5
Console.WriteLine(Convert.ToString(number, 2).PadLeft(16, "0"c))
Dim lastNbits As Integer = get_last_N_bits(number, N)
Console.WriteLine(Convert.ToString(lastNbits , 2).PadLeft(16, "0"c))
End Sub
End Class
' run:
'
' 0000000110111001
' 0000000000011011
'