Вывести числа, которые содержатся в первом массиве и не содержатся во втором

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim A(12) As Integer
        Dim B(10) As Integer
        Dim i, j As Integer
        Randomize()
        Label1.Text = ""
        Label2.Text = ""
        Label3.Text = ""
        For i = 1 To 12
            A(i) = 1 + (20 * Rnd())
            Label1.Text = Label1.Text + Str(A(i))
        Next
        For j = 1 To 10
            B(j) = 1 + (20 * Rnd())
            Label2.Text = Label2.Text + Str(B(j))
        Next
 
    End Sub
 
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim A(12) As Integer
        Dim B(10) As Integer
        Dim i, j, r As Integer
        
        For i = 1 To 12
            r = 0
 
        Next
        For j = 1 To 10
            If A(i) = B(j) Then
                r = 1
            End If
 
            If r = 0 Then Label3.Text = Label3.Text + A(i)
        Next
    End Sub
End Class

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'объявить общими и убрать из первой процедуры
'Dim A(12) As Integer
'Dim B(10) As Integer
Dim i, j, r As Integer, b as boolean
  For i = 1 To 12
     r = A(i): b=true
     For j = 1 To 10
       If r = B(j) Then b=false:exit for
     Next j
     If b Then Label3.Text = Label3.Text +r
  Next i
End Sub