VB中,有1-39个数字,任意随机选择其中某些数字（数量不限）然后两两组合,请问用VB该怎么写程序?

Private Sub Form_Load()
Dim i As Integer
Dim a() As Integer
Randomize
s = Int(10 * Rnd)
ReDim a(s)
For i = 0 To s '任意选择数量
p = Int(39 * Rnd)
a(i) = p
Text1.Text = Text1.Text & " " & p '随机数
Next i
Text1.Text = Trim(Text1.Text)
For d = 0 To s
For t = d + 1 To s
Text2.Text = Text2.Text & " " & a(d) & a(t)
Next t
Text2.Text = Text2.Text & vbCrLf
Next d
End Su