1. (2019高二下·嘉兴期末) 在平面坐标系中，A点坐标为(25,35)，编写VB程序，计算一组给定点中，距离A点的最小距离。在文本框Text1中依次输入一组给定的坐标值，如3个点的坐标(10,15)、(45,18)、(32,40)输入示例如图所示，坐标值以逗号分隔、逗号结尾，单击“计算”按钮Command1后，程序运行结果显示在Label3中。

实现上述功能的VB程序如下，请在划线处填入合适代码。

Private Sub Command1_Click()

  Dim i As Integer, n As Integer

  Dim x As Single, y As Single, x1 As Single, y1 As Single

  Dim d As Single, min As Single

  Dim s As String, t As String

  s = Text1.Text:   x = 25: y = 35                       'A点坐标

  n = 0: min = -1: t = ""

  For i = 1 To

    If Mid(s, i, 1) = "," Then

      n = n + 1

      If Then

         x1 = Val(t)

      Else

         y1 = Val(t)

         d =

         If min = -1 Then min = d

         If d < min Then min = d

      End If

      t = ""

    Else

      t = t + Mid(s, i, 1)

    End If

  Next i

  Label3.Caption = Str(min)

End Sub