15.如圖所示加密程序:在文本框Text1中輸入明文,單擊命令按鈕“加密”,在文本框Text2中輸出密文。加密算法思路如下:1、只針對(duì)英文字符和數(shù)字進(jìn)行加密,其余字符不變;2、將原文中的小寫字母轉(zhuǎn)換為大寫字母;3、根據(jù)第2步所得結(jié)果,若是英文字符,則逐個(gè)后移4位(例如:A->E,Z->D),若是數(shù)字,則逐個(gè)前移2位(例如:3->1,1->9)。 綜上所述:原文為Jim is at room 4!,加密后輸出密文為:NMQ MW EX VSSQ 2! (1)該程序單擊命令按鈕“加密”事件處理過程名為
(2)程序代碼如下,請(qǐng)?zhí)羁?br /> Private Sub Cmd1_Click
Dim str1 As String,str2 As String,ch As String Dim i As Integer,j As Integer,n As Integer str1=Text1.Text str2=““ n=Len(Text1.Text) For i=1 To n ch=Mid(str1,i,1) If
Then ch=Chr((Asc(ch)-32)) End If If ch>=“A“And ch<=“Z“Then ch=Chr((Asc(ch)-Asc(“A“)+4)Mod 26+Asc(“A“)) ElseIf ch>=“0“And ch<=“9“Then ch=
End If
Next i Text2.Text=str2 End Sub (3)若在Text1中輸入的明文為:Num 15*,則程序運(yùn)行后在Text2中輸出的密文為:
16.羅列對(duì)分查找中可能查到的中點(diǎn)。對(duì)分查找是我們常用的查找方式。在對(duì)分查找過程中,計(jì)算中點(diǎn)是非常重要的步驟。以下程序?qū)崿F(xiàn)了“羅列對(duì)分查找中可能查到的中點(diǎn)”的功能。算法如下:用戶在文本框Text1中輸入模擬對(duì)分查找數(shù)據(jù)的個(gè)數(shù)n,單擊“產(chǎn)生隨機(jī)數(shù)并升序排列”按鈕,在List1中顯示n個(gè)不重復(fù)且已經(jīng)升序排列的數(shù)(范圍[1,100]),單擊“可能查到的中點(diǎn)”,在list2中分行顯示各個(gè)可能查到的中點(diǎn) (1)實(shí)現(xiàn)上述功能的VB程序如下,請(qǐng)?jiān)跈M線處填入合適代碼。 Private Sub Command1_Click ( ) Dim i As Integer Randomize For i=1 To 100 f(i)=False Next i n=Val(Text1.Text) For i=1 To n t=Int(Rnd*100+1) Do While f(t)=True
Loop f(t)=True Next i j=0 For i=1 To 100 If
Then j=j+1 a(j)=i List1.AddItem Str(i) End If Next i End Sub Private Sub Command2_Click ( ?。?br />Dim b(1 To 100)As Integer,k As Integer,c As Integer,max As Integer Dim s As String Dim j As Integer n=Val(Text1.Text) max=0 For k=1 To n i=1:j=n:c=0 Do While i<=j m=(i+j)\2:c=c+1 If c>max Then max=c If m=k Then b(m)=c:Exit Do If m<k Then i=m+1 Else j=m-1 Loop Next k For i=1 To max s=““ For j=1 To n If
Then s=s+Str(a(j)) Else s=s+““ End If Next j List2.AddItem s Next i End Sub (2)當(dāng)數(shù)據(jù)是11,22,33,44,55,66,77,88,99時(shí),第3行第3個(gè)數(shù)為