程序代码如下：

Private Sub Command1_Click()

Dim Sname As String, Skey As String    ‘Sname 保存姓名，Skey保存关键字

Dim i As Integer, j As Integer, n As Integer   ‘n关键字的长度

Skey = Text1.Text

n = Len(Skey)

List2.Clear

For i = 1 To List1.ListCount     ‘ListCount是列表框中项目的个数

    Sname = List1.List(i - 1)     ‘将List1中的第i-1项赋值给Sname

    For j = 1 To     ①   

    If Skey =     ②       Then

        List2.AddItem Sname

        Exit For

    End If

    Next j

Next i

If      ③     = 0 Then List2.AddItem "没有找到带<" & Skey & ">的名字。"

End Sub

Private Sub Command1_Click()

Dim sum As Double, x As Double

 sum = 0

 n = 0

 For i = 1 To 5

  x = n / i

  n = n + 1

  sum = sum + x

 Next

End Sub

该程序通过For循环计算sum的值，下列表达式的值与sum相等的是（  ）

实现上述功能的VB程序如下，请在划线处填入合适的代码。

Private Sub Command1_Click()

Dim s1 As String

Dim s2 As String

Dim s3 As String

Dim l1 As Integer

Dim l2 As Integer

Dim l3 As Integer

Dim a(1 To 100) As Integer

Dim b(1 To 100) As Integer

Dim c(1 To 100) As Integer

Dim t As Integer

s1 = Text1.Text

s2 = Text2.Text

l1 = Len(s1)

l2 = Len(s2)

For i = l1 To 1 Step -1

 a(i) ={#blank#}1{#/blank#}

Next

For i = l2 To 1 Step -1

 b(i) =Val(Mid(s2, l2 - i + 1, 1))

Next

If l1 > l2 Then l3 = l1 Else l3 = l2

t = 0

For i = 1 To l3

  c(i) = a(i) + b(i) + t

  t = c(i) \ 10

  c(i) ={#blank#}2{#/blank#}

Next

For i = 1 To l3

  s3 = Str(c(i)) + s3

Next

If{#blank#}3{#/blank#}Then s3 = “1” + s3

Text3.Text = s3

End Sub