05年秋江苏计算机二级VB上机试题及答案

江苏省等级考试二级VB上机试卷2005年（秋）及参考答案【题目1】本程序的功能是：找出2~10000之间可以表示成2²-1形式的素数.本题程序界面见图1.
答：
源程序：
Option Explicit
Private Sub Command1_Click()
Dim Exp As Integer, Idx As Integer
For Idx = 2 To 10000
If Mersenne(Idx, Exp) Then
If Prime(Idx) Then
List1.AddItem Idx & " =" & 2 & "^" & Exp & "-1"
End If
End If
Exp = 0
Next Idx
End Sub
Private Function Mersenne(N As Integer, Exp As Integer) As Boolean
Dim M As Integer, Ex As Long
M = N
Ex = 1
Do While M > Ex
Exp = Exp + 1
Ex = Ex * 2
Loop
If M = Ex - 1 Then
Mersenne = True
End If
End Function
Private Function Prime(N As Integer) As Boolean
Dim K As Integer
For K = 2 To Sqr(N)
If N Mod K = 0 Then Exit Function
Next K
Prime = True
End Function
【题目2】将1～9这9个数字顺序排列围成一圈,从中任意一个数字开始,依次将其分成三段,每段数字连
在一起算一个数,得到一个2位数、一个3位数和一个4位数,将这三个数相加,使其和数能被77整除.编写一个能找出这三个数的程序.
【编程要求】
1.程序参考界面如图2所示,编程时不得增加或减少界面对象或改变对象的种类,窗体及界面元素大小适中,且均可见;
2.单击“运行”按钮,找出符合条件的三个数,并将它们显示在文本框中;
3.单击“清理”按钮,则将文本框清空,并将焦点设置在“运行”按钮上;单击“结束”按钮,结束程序运行;
4.程序中必须包含一个将数字分段,得到一个2位数、一个3位数和一个4位数的通用过程.
答：
源程序：
Private Sub Command1_Click()
Dim s As String, i As Integer, sum As Integer, s1 As Integer, s2 As Integer, s3 As Integer s = ""
For i = 1 To Len(s)
Call part(s, i, s1, s2, s3)
If (s1 + s2 + s3) Mod 77 = 0 Then
Text1.Text = Text1.Text & "( " & s1 & " + " & s2 & " + " & s3 & " ) mod " & 77 & "=0" & vbCrLf
End If
Next i
End Sub
Private Sub part(ByVal s As String, i As Integer, s1, s2, s3)
s = s & s
s1 = Int(Mid(s, i, 2))
s2 = Int(Mid(s, i + 2, 3))
s3 = Int(Mid(s, i + 5, 4))
End Sub
Private Sub Command2_Click()
End
End Sub
3
[题目3]下面程序的功能是将给定的十六进制整数转换成二进制整数（删除高位0）。

答：
源程序：
Option Explicit
Private Sub Command1_Click()
Dim H As String, Bin As String, L As Integer, I As Integer
Dim K As Integer, S As String * 1
H = UCase(Trim(Text1))
L = Len(H)
For I = 1 To L
S = Mid(H, I, 1)
If S <= "9" And S >= "0" Then
K = Val(S)
Else
K = Asc(S) - 55
End If
If K < 0 Or K > 15 Then
Bin = "十六进制数据错误"
End If
Call Trans(Bin, K)
Next I
Bin = Right(Bin, Len(Bin) - InStr(Bin, "1") + 1)
End Sub
Private Sub Trans(Bin As String, K As Integer)
Dim S As String, I As Integer, N As Integer
Do While K > 0
S = K Mod 2 & S
K = K \ 2
Loop
S = "0000" & S
Bin = Bin & Right(S, 4)
End Sub
[题目4]编写程序，找出由1，2，3，4四个不同数字组成的4位整数中的素数。

[编程要求]
1程序参考界面如图2所示，编程时不得增加或减少界面对象或改变对象的种类，窗体及界面元素大小适中，且均可见；
2单击“开始”按钮，生成（或筛选出）由1，2，3，4四个数字组成的4位整数，并显示在列表框List1中，在列表框List2中显示其中的素数；
3单击“清理”按钮，则将两个列表框清空；单击“退出”按钮，结束程序运行；
4程序中必须包含一个判断某数是否为素数的通用过程。

答：
5
Private Sub Command1_Click()
Dim i As Integer, j As Integer, k As Integer, t As Integer, s As String
For i = 1 To 4
For j = 1 To 4
For k = 1 To 4
For t = 1 To 4
If i <> j And i <> k And i <> t And j <> k And j <> t And k <> t Then s = i & j & k & t
List1.AddItem s
If prime(Int(s)) Then List2.AddItem s
End If
Next t
Next k
Next j
Next i
End Sub
Private Function prime(ByVal x As Integer) As Boolean
Dim i As Integer
prime = True
For i = 2 To Sqr(x)
If x Mod i = 0 Then prime = False: Exit Function
Next i
End Function
Private Sub Command2_Click()
List1.Clear
List2.Clear
End Sub
Private Sub Command3_Click()
End
End Sub
[题目5]下面程序的功能是：从由2，4，5，7四个数字组成的没有重复数字的24个四位数中，找出一个具有倍数关系的四位数对。

本题程序界面如图1。

答：
源程序：
Option Explicit
Private Sub Compare(A() As Integer, S As String, Idx As Integer)
Dim I As Integer, J As Integer
For I = 1 To Idx
For J = 1 To Idx
If A(I) Mod A(J) = 0 And J <> I Then
S = A(I) & "是" & A(J) & "的" & A(I) \ A(J) & "倍" & vbCrLf
Text1 = S
Exit Sub
End If
Next J
Next I
End Sub
7
Private Sub Command1_Click()
Dim N(100) As Integer, I As Integer, S As String, Idx As Integer
Dim J As Integer, Ch As String * 1, K As Integer
For I = 2457 To 7542
S = CStr(I)
For J = 1 To 4
Ch = Mid(S, J, 1)
If Ch <> "2" And Ch <> "4" And Ch <> "5" And Ch <> "7" Then Exit For
K = J
Do
K = K + 1
If Ch = Mid(S, K, 1) Then Exit For
Loop Until K > 4
Next J
If J > 4 Then
Idx = Idx + 1
N(Idx) = I
List1.AddItem I
End If
Next I
Call Compare(N, S, Idx)
End Sub
[题目6]编写程序：生成两个等差数列A={3，10，17，24，31，……，108}与B={3，8，13，18，23，……，108}，再找出两个数列中的相同项。

[编程要求]
1. 程序参考界面如图2所示，编程时不得增加或减少界面对象或改变对象的种类，窗体及界面元素大小适中，且均可见；
2. 单击“运行”按钮，生成这两个数列，分别输出到多行文本框1与多行文本框2中，找出两个数列中的相同项，并输出到文本框3中；
3. 单击“清除”按钮，则将文本框清空，并将焦点置于“运行”按钮上；单击“结束”按钮，结束程序运行；
4.程序中必须包含一个生成等差数列的通用过程。

答：
源程序：
Option Base 1
Private Sub Command1_Click()
Dim d1() As Integer, d2() As Integer, n1 As Integer, n2 As Integer, i As Integer, j As Integer Call scdcsl(d1, 3, 7, 108, n1)
Call scdcsl(d2, 3, 5, 108, n2)
For i = 1 To n1
Text1 = Text1 & d1(i) & " "
Next i
For i = 1 To n2
Text2 = Text2 & d2(i) & " "
Next i
i = 1
j = 1
9
Do
If d1(i) = d2(j) Then
Text3 = Text3 & d1(i) & " "
i = i + 1
j = j + 1
ElseIf d1(i) > d2(j) Then
j = j + 1
Else
i = i + 1
End If
Loop Until (i > n1)
End Sub
Private Sub scdcsl(a() As Integer, x As Integer, d, y , n) Do
n = n + 1
ReDim Preserve a(n)
a(n) = x
x = x + d
Loop While (x <= y)
End Sub
Private Sub Command2_Click()
Text1.Text = ""
Text2.Text = ""
Text3.Text = ""
Command1.SetFocus
End Sub
Private Sub Command3_Click()
End
End Sub
[题目7]下面程序的功能是，找出1~300之间的三个相临整数N ，N+1和N+2，且每个整数均为两个素数的乘积。

本题程序界面如图1。

答：
源程序：
Option Explicit
Private Sub Command1_Click()
Dim p() As Integer, i As Integer, N(3) As Integer
Call Prime(p, 150)
For i = 1 To 300
If Compare(p, i) Then
List1.AddItem i & "," & i + 1 & "," & i + 2
End If
Next i
End Sub
Private Sub Prime(p() As Integer, N As Integer)
Dim i As Integer, k As Integer, idx As Integer
For i = 2 To N
11
For k = 2 To Sqr(i)
If i Mod k = 0 Then Exit For
Next k
If k > Sqr(i) Then
idx = idx + 1
ReDim Preserve p(idx)
p(idx) = i
End If
Next i
End Sub
Private Function Compare(p() As Integer, ByVal a As Integer) As Boolean Dim i As Integer, J As Integer, k As Integer, Flg As Boolean
For k = 1 To 3
i = 1
Do While i <= UBound(p)
For J = 1 To UBound(p)
If a = p(i) * p(J) Then Exit Do
Next J
i = i + 1
Loop
If J > UBound(p) Then Exit Function
a = a + 1
Next k
Compare = True
End Function
[题目8]编写程序求给定正整数的所有因子及所有因子的倒数之和。

[编程要求]
1．程序参考界面如图2所示，编程时不得增加或减少界面对象或改变对象的种类，窗体及界面元素大小适中，且均可见；
2．运行程序，在文本框1中输入测试数据，单击“运行”按纽，求出其所有因子及所有因子的倒数和，按图示格式输出到多行文本框2中（结果要进行约分）；
3．单击“清除”按纽，则将两个文本框清空，焦点置于文本框1上；
4．程序中必须包含一个求其正整数所有因子倒数之和的通用过程。

答：
源程序：
Private Sub Command1_Click()
Dim x As Long
x = Int(Trim(Text1.Text))
Text2.Text = x & "的所有因子为："
Call yzsum(x)
End Sub
Private Sub yzsum(ByVal x As Long)
Dim a() As Integer, idx As Integer, fz As Long, s1 As Long, fm As Long, s2 As Long
Dim i As Integer
For i = 1 To x
If x Mod i = 0 Then
13
idx = idx + 1
ReDim Preserve a(idx)
a(idx) = i
Text2 = Text2 & i & " "
If fm = 0 Then
fm = fm + i
fz = 1
Else
s1 = gcd(fm, i)
s2 = fm * i / s1
fz = fz * s2 / fm + s2 / i
fm = s2
End If
End If
Next i
s1 = gcd(fm, fz)
fz = fz / s1
fm = fm / s1
If fm = 1 Then
Text2 = Text2 & vbCrLf & "所求因子倒数之和为： " & fz
Else
Text2 = Text2 & vbCrLf & "所求因子倒数之和为： " & fz & "/" & fm End If
End Sub
Private Function gcd(ByVal x As Long, ByVal y As Long) As Long
Dim r As Long
Do
r = x Mod y
x = y
y = r
Loop Until (y = 0)
gcd = x
End Function
Private Sub Command2_Click()
Text1.Text = ""
Text2.Text = ""
Text1.SetFocus
End Sub
15。