实现该功能的VB程序如下，但加框处代码有错，请改正。

Const n = 10

Dim a(1 To n) As Integer

Private Sub Form_Load()

    随机产生 n 个不重复的整数存数组 a，并在列表框 list1 中显示。代码略。

End Sub

Private Sub Command1_Click()

    Dim i As Integer, j As Integer, t As Integer

    Dim imin1 As Integer, imin2 As Integer

    For i = 1 To n \ 2

      imin1 = i: imin2 = i + 1

    If a(imin1) > a(imin2) Then t = imin1: imin1 = imin2: imin2 = t

    For j = i + 2 To n - i + 1

      If a(j) < a(imin1) Then

      imin2 = imin1: imin1 = j

      '①

      imin2 = j

    End If

Next j

If i <> imin1 Then t = a(i): a(i) = a(imin1): a(imin1) = t

If imin2 = i Then    '②

If n - i + 1 <> imin2 Then

    t = a(n - i + 1): a(n - i + 1) = a(imin2): a(imin2) = t

End if

Next i

For i = 1 To n

      Text2.Text = Text2.Text + Str(a(i))

Next i

End Sub

①{#blank#}1{#/blank#}  ②{#blank#}2{#/blank#}

a(1)=6:a(2)=8:a(3)=7:a(4)=3:a(5)=1:a(6)=2:a(7)=5:a(8)=4

i = 1: j = 8

key = a(1)

Do While i < j

 Do While i < j And a(j) >= key

  j = j - 1

 Loop

 a(i) = a(j)

 Do While i < j And a(i) <= key

  i = i + 1

 Loop

 a(j) = a(i)

Loop

a(i) = key

For i = 1 To 8

 Label1.Caption=Label1.Caption++Str(a(i))

Next i

执行该程序段，标签Label1上显示的内容是(  )

n = 0 : i =1 : j = 7

Key = Val(Textl.Text)

f = False

Do While i <= j And Not f

   m = fix((i + j)/2+0.5)

   n = n + 1

       If key = d(m) Then

          f = True

       Elseif key > d(m) then

          j = m - 1

   Else

          i = m + 1

       end if

Loop

a=[27,5,25,36,78]

f=[False]*5

i=0

while i<4 and not f[i]:

    for j in range(4, i, -1):

        if a[j]<a[j-1]:

            a[j], a[j-1]=a[j-1], a[j]

            f[i]=True

    i+=1

执行该程序段后，数组f中值为True的元素个数是（   ）