怎么用VB编一个程序

这样循环的话会很慢！
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim a, b, c, d, f, g As Integer
a = 1 : b = 1 : c = 1 : d = 1 : f = 1 : g = 1
For a = 1 To 50
For b = 1 To 50
For c = 1 To 50
For d = 1 To 50
For f = 1 To 50
For g = 1 To 50
If a + b + c + d + f + g <= 100 And a + b + c + d + f + g >= 80 Then
If (a + b + c + d + f + g) Mod 2 = 0 Then
Label1.Text = Label1.Text + Str(a) + Str(b) + Str(c) + Str(d) + Str(f) + Str(g)
Label1.Text = Label1.Text + Chr(10) + Chr(13)
Else
Label2.Text = Label1.Text + Str