填空题

程序如下:
Private Sub Form_Click( )
  Const PI = 3.14159
  Dim r As Single, S As Single
  R = InputBox("请输入圆的半径","输入数据","50")
  S = PI*r*r
  Print "S = "; Format(S,"###,###.##")
End Sub
程序运行后,单击窗体,将显示一个输入对话框,输入35,则单击"确定"按钮后,输出结果为______。

【参考答案】

S=3,848.45