内容正文:
专题8 VB综合应用之算法程序设计(专项练习)
1. 有一段 VB 程序,代码如下:
For i = 1 To 3
For j = 8 To i + 1 Step -1
If a(j) < a(i) Then
t = a(j): a(j) = a(i): a(i) = t
End If
Next j
Next i
数组元素a(1)到 a(8)的值依次为“35,18,14,20,30,15,28,26”,运行该程序段后,a(5)到 a(8)的值依次是( )
A. 30,26,28,35 B. 14,15,18,20
C. 26,15,18,14 D. 26,28,30,35
2. 有如下程序:
const n=10
dim a(1 to 10 ) as integer, i as integer
s=0
i=1
Do while a(i)>0 and i<= n
s=s+1
i=i+1
loop
数组元素a(1)至a(10)的数据依次为“1,5,2,3,8,-9,5,6,7,-10”,运用该算法处理后s的值是( )
A. 3 B. 5 C. 8 D. 10
3. 有如下程序:
S=“”
For i=1 to 3
For j=7 to i+1 step -1
If a(j)<a(j-1) then
K=a(j):a(j)=a(j-1):a(j-1)=k
End if
Next j
s=s+str(a(i))
Next i
Text1.text= s
数组元素a(1)到a(7)的数据依次为“4,15,11,7,9,16,12”经过该程序段“加工”后,文本框text1中显示的内容是( )
A. 4 7 9 B. 16 15 12
C. 4 15 11 7 D. 4 7 9 11
4. 有如下程序段:
For k = 1 To 4 Step 3
For i = k To k + 1
For j = i + 1 To k + 2
If a(j) < a(i) Then
temp = a(j): a(j) = a(i): a(i) = temp
End If
Next j
Next i
Next k
数组元素a(1)到a(6)的值依次为“9,8,7,6,5,4”,经过该程序段“加工”后,数组元素a(1)到a(6)的值依次为( )
A. 9,8,7,6,5,4 B. 4,5,6,7,8,9
C. 7,8,9,4,5,6 D. 9,8,7,4,5,6
5. 有如下程序段:
For i = 1 To 2
For j = 5 To i + 1 Step -1
If a(j) > a(j-1) Then
t = a(j): a(j) = a(j-1): a(j-1) = t
End If
Next j
Next i
数组元素a(1)到a(5)的值依次为“33,24, 45, 16, 77”,经过该程序段“加工”后,数组元素a(1)到a(5)的值依次为( )
A. 77,45,33, 24,16 B. 16, 24,33, 45, 77
C. 77, 45, 24,16,33 D. 16,24,45,33,77
6. 以下VB代码运行后,在文本框Textl中输入1,则选择语句If k<= 9 Then k = k + i执行的次数为( )
Private Sub Text1_Change()
Dim k As Integer, i As Integer
k = Val(Text1.Text)
For i = 1 To 3
If k <= 9 Then k = k + i
Next i
Text1.Text = Str(k)
End Sub
A. 3 B. 5 C. 6 D. 9
7. 有一组升序排列的数:3、6、7、10、12、17、26、31、79,如果用对分法查找数据10,则依次访问的数据为( )
A. 12、6、7、10 B. 12、7、10 C. 12、6、10 D. 12、7、6、10
8. 字符串中任意连续的字符组成的子序列称为该字符串的子串,如字符串“abc”的子串有“a”“b”“c”“ab”“bc”“abc”。输出字符串s所有子串的VB程序段如下:
Private Sub Commandl_Click()
Dim s As String,slen As Integer
Dim I As Integer,j As Integer
s = Textl. Text
slen= Len(s)