Private Sub Command1_Click()

    Dim n As Integer, L As Integer, t As Integer

    Dim i As Integer, j As Integer, k As Integer

    Dim s As String, result As String

    Dim a(1 To 50) As Integer, dir(1 To 50) As Integer

    L = Val(Text1.Text): n = Val(Text2.Text): t = Val(Text3.Text) s = Text4.Text

    s = s + ".": tmp = 0: k=0

    For i = 1 To Len(s)

        ch = Mid(s, i, 1)

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

            tmp = tmp * 10 + Val(ch)

        Else

            k = k + 1

            a(k) = tmp: dir(k) = 1

            tmp = 0

        End If

    Next i

    For i = 1 To t

       For j = 1 To n

            IfThen dir(j) = -dir(j)

            Else

                For c = 1 To n

                    IfThen dir(c) = (-1) * dir(c)

                    dir(j) = (-1) * dir(j)

                End If

            Next c

        End If

    Next j

    Next i

    For i = 1 To n

        result = result + Str(a(i))

    Next i

    Label5.Caption = Str(t) + "秒后小球的位置为：" + result

End Sub