首先,分别求出特加密ASCII字符的ASCII码,然后用7位二进制来表示,比如“4”的ASCII码为十进制52,转换为7位二进制为“0110100”
其次,从左至右依次记为第1、2、3....7位,分别把第3、4、5位取反,即0变1, 1变0,至此“0110100”变为“0101000”,将此二进制转换为ASCII码为40,对应的字符为“(”,即“4”经过加密后得到加密字符左括号“(”。
在文本框Text1中输入ASCII字符,单击命令按钮Command,则在文本框Text2中显示经过加密的字符。VB代码如下,程序界面如图所示。

上述加密与解密过程实际上是可以互逆的,请完成下列问题。
Private Sub Command1_Click()
Dim a(1 To 7) As Integer
Dim i As Integer, j As Integer, n As Integer
Dim ascl As String, s As String, s1 As String
i=1
S=Text1.Text
Text2.Text=“”
Do While i=Len(Text1.Text)
s1= Mid(s, i, 1)
ascl=Asc(s1)
n=0
For j=7 To 1 Step-1
If j=3 Or i=4 Or j=5 Then
a(j)=
Else
a(j) = asc1 Mod 2
End If
ascl=asc1\2
n=
Next j
Text2.Text =Text2.Text+
i=i+1
Loop
End Sub
Private Sub Command1_Click()
Dim s As String, s1 As String, h As String
Dim n As Integer
s = Text1.Text
n =
h = Mid(s, 1, 1)
If n > 16 Then
Label1.Caption = "长度超过16个字符!"
ElseIf
Then
Label1.Caption = "不是以小写字母开头!"
Else
For i = 2 To n
s1 =
If s1 < "0" Or s1 > "9" Then
Label1.Caption = "非首位不是数字字符!"
Else
Label1.Caption = "该帐户名可用。"
End If
Next i
End If
End Sub
s=Text1.Text
s1= “ ”
For i=1 To Len(s)
c=Mid(s,i,1)
If c>=“A” And c<=“Z” Then
c=Chr(Asc(c)+32)
Elself c>=“a” And c<=“z” Then
c=Chr(Asc(c)-32)
End If
s1=c+s1
Next i
Text2.Text=s1
该程序段运行后,若在文本框Text1中输入“Ab12CD”,则文本框Text2中显示的内容是( )
a="10001": b=0:t=0
For i=1 To Len(a)
c= Mid(a, i, 1)
If c="0" Then t = t -1 Else t = t +1
If t < 0 Then b = b * 2 Else b = b * 2+1
Next i
执行该程序段后,变量b的值为( )
s = Text1.Text: n = Len(s): Count = 0
For i=1 To n\2
If Mid(s, i, 1) <> Mid(s, n-i+1, 1) Then
Count = Count + 1
End If
Next i
若在文本框Text1中输入字符串“200good2”,则Count的值为( )
Private Sub Command1_Click()
Dim zfc As String '用于存储输入的字符串
Dim ans As String '用于存储处理后的字符串
Dim i As Integer,ch As String
Dim n As Intege r'用于存储输入的字符串的长度
①
n=Len(zfc)
i=1
Do While i<=n
②
If ch>="0"And ch<="9"Then
i=i+1
Else
③
i=i+1
End If
Loop
Label2.Caption="结果为:"+ ④
End Sub
画线处应填入的代码为:①;②;③;④。
for x in range(0,21):
for y in range(0,34):
方框内代码可以为:
if x+y+z==100 and 5*x+3*y+z/3==100:
print("鸡翁",x,"鸡母",y,"鸡雏",z)
B . for z in range(0,101,3):if x+y+z==100 and 5*x+3*y+z/3==100:
print("鸡翁",x,"鸡母",y,"鸡雏",z)
C . z=100-x-yif 5*x+3*y+z/3==100:
print("鸡翁",x,"鸡母",y,"鸡雏",z)
D . z=(100-x-y)/3if 5*x+3*y+z/3==100:
print("鸡翁",x,"鸡母",y,"鸡雏",z)