实现以上功能的VB程序如下,在横处填入合适的代码。

Dim a(1 To 20) As Integer     ‘存储区间的左端点数值

Dim b(1 To 20) As Integer     ‘存储区间的右端点数值

Private Sub Form_Load()

‘将区间左端点存入数组a,区间右端点存入数组b,并在列表框List1显示,代码略

End Sub

Private Sub Command1_Click()

Dim i As Integer, j As Integer

Dim curL As Integer, curR As Integer

For i=1 To n-1

 For j=1 To n-i

  If{#blank#}1{#/blank#}Then

   t=a(j): a(j)=a(j+1): a(j+1)=t

   t=b(j): b(j)=b(j+1): b(j+1)=t

  End If

 Next j

Next i

curL=a(1): curR=b(1)

For i=2 To n

 If{#blank#}2{#/blank#}Then

  If curR < b(i) Then{#blank#}3{#/blank#}

 Else

  List2.AddItem“["+Str(curL)+Str(curR)+"]”

  curL=a(i): curR=b(i)

 End If

Next i

List2. AddItem “[”+Str(curL)+Str(curR)+“]”

End Sub

实现上述功能的VB程序如下，但加框处代码有错，请改正。

Const n = 10

Const maxn = 20

Dim a(1 To n) As Integer, index(1 To n) As Integer, flag(1 To n) As Boolean

Private Sub Form_Load()

Dim i As Integer

Randomize

For i = 1 To n

 flag(i) = False

 a(i) = Int(Rnd() * maxn) + 1

 List1.AddItem Str(a(i))

Next i

End Sub

Private Sub Command1_Click()

Dim i As Integer, j As Integer

Dim k As Integer

For i = 1 To n

 For j = 1 To n

  If flag(j) = False Then k = j: Exit For

 Next j

 For m = k + 1 To n

  If Then k = m     ‘⑴

 Next m

 index(i) = k

 flag(k) = True

Next i

For i = 1 To n

 List2.AddItem      ‘⑵

Next i

End sub

⑴{#blank#}1{#/blank#} ⑵{#blank#}2{#/blank#} 

Dim n As Integer

Dim a(1 To 100) As Integer

Dim b(1 To 100) As Integer

Private Sub Form Load()

‘读取若干数据依次存储到数组a中，并将数据元素的总个数存储到变量n中。

‘将每段数据的元素个数及排序的次序依次存储到数组b中；

‘b(1)、b(2)分别存储第1段数据的元素个数、排序的次序，

‘b(3)、b(4)分别存储第2段数据的元素个数、排序的次序，.....

“代码略。

End Sub

Private Sub Command1_Click())

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

    Dim pb As Integer, endpos As Integer

    pb=1: endpos =b(1)

    For i=1 To n-1

        If i=endpos Then

            pb=pb+2:i=endpos+1

               ①  

        End If

        k=i

        For j =i+1 To endpos

            If  Then k=j     ‘⑵

        Next j

        If k<>i Then

                ②  

        End If

    Next i

    Text3.Text =""     ‘⑷

    For i=1 To n

        Text3.Text=Text3.Text + Str(a(i))

    Next i

End Sub

For i = 1 To 5

 k = i

 For j = i + 1 To 6

  If a(k) > a(j) Then k = j

 Next j

 t = a(k): a(k) = a(i): a(i) = t

 b((i + 2) Mod 6 + 1) = a(i)

Next i

i=1

Do While i<=5

    If i = 0 or a(i - 1)<= a(i) Then

        i=i+1

    Else

        t=a(i): a(i)=a(i-1): a(i-1)=t

        i=i-1

    End If

Loop

数组元素a(0)到a(5)依次为：“0，41，22，53，99，36”，经过该程序段处理后，数组元素a(3)的值为（   ）