Const n = 15

Private Sub Command1_Click()

  Dim a(1 To n) As Integer  '数组a存放不同颜色袜子的数量，默认值为0

  Dim s As String, ch As String

  Dim c As Integer, i As Integer, t As Integer

    List1.Clear

    s = Text1.Text

    t = 0 ：c = 0 : i = 1

    Do While i <= Len(s)

        ch = Mid(s, i, 1)

        If ch >= "0" And ch <= "9" Then

            t = t * 10 + Val(ch)

        Else

            a(t) =   ①  

            t = 0

        End If

        i = i + 1

    Loop

    For i = 1 To n

        If   ②    Then List1.AddItem "落单袜子的颜色为" + Str(i)

        c =

    Next i

    Label1.Caption = "能配对的袜子有" + Str(c) + "双"

End Sub

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