s = "": k = 0
For i = 1 To 20 Step 3
If i Mod 7 = 0 Then
k = 1
ElseIf i Mod 5 = 0 Then
k = 2
End If
If i Mod 2 = 0 Then k = 3
s = s + Str(k)
Next i
Label1.Caption = s
该程序段运行后,标签框label1上显示的内容是( )