某学校进行问卷调查，共n个班级，现将参与问卷调查的学生名单在文本框Text1中按照“班级编号+姓名”的方式连续输入。单击“查询”按钮，统计每个班参与问卷调查的人数。在列表框List1中按“参与人数”降序输出，当“参与人数”相同时，按班级编号升序输出。程序运行界面如图。实现上述功能的VB程序段如下：

Private Sub Search_Click()

    Const n = 12

    Dim s As String, c As String

    Dim i As Integer, t As Integer

    Dim rs(0 To n) As Integer       '数组rs存储班级人数

    Dim bj(1 To n) As Integer       '数组bj存储班级编号

    Dim flag As Boolean

    s = Text1.Text

    t = 0

    For i = 1 To Len(s)

        c = Mid(s， i， 1)

        If c >= "0" And c <= "9" Then

            t =     ①       

            flag = True

        ElseIf flag = True Then

            rs(t) = rs(t) + 1

            flag = False

            t = 0

        End If

    Next i

    For i = 1 To n

        bj(i) = i

    Next i

    For i = 1 To n-1

        k = i

        For j = i + 1 To n

            If      ②      Then k = j

        Next j

        If k <> i Then

            t = rs(k): rs(k) = rs(i): rs(i) = t

            t = bj(k): bj(k) = bj(i): bj(i) = t

        End If

    Next i

    For i = 1 To n

        List1.AddItem Str(bj(i)) + "班有：" + " " +  + "人"

    Next i

End Sub