c语言 从100顺次减到1,对n项（n<=100）数据序列的前x项求和，可设计如下算法：将数据序列存储在数组a中，并按一定规则转换成数组c，再借助数组c实现求和. 将数组a转换成数组c的方法描述如下...

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编写VB程序，实现如下功能：单击“生成密文”按钮Command2，在文本框Text3中产生与每个小写字母对应的密文(每个明文字母对应1个不重复的密文字母)。在文本框Text1中输入单词字符串，单击“加密”按钮Command1后，进行逐个字符加密，加密方法：在“明文”中找到相应字符，再得到明文对应位置的密文,并在文本框Text2中显示对应密文(运行效果如图所示)。实现上述功能的VB代码如下：

Dim m2 As String

Private Sub Command1_Click()

Dim flag(1 To 26) As Boolean

Dim num As Integer,t As Integer

Randomize

num = 1

Text3.Text = " "

For i =1 To 26

flag(i) = False

Next i

Do While num <= 26

x = Int(Rnd * 26) + 97

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If flag(t) =False Then

m2 = m2 + Chr(x)

num =num + 1

②

End If

Loop

Text3.Text = m2

End Sub

Private Sub Command2_Click()

Dim s As String， m As String， result As String

Dim k As String， c As Integer

s = Text1.Text

m = "abcdefghijklmnopqrstuvwxyz"

For i = 1 To Len(s)

k = Mid(s, i, 1)

If k >= "A" And k <= "Z" Then

k = Chr(Asc(k) + 32)

End If

c =1: continue = True

Do While ③

If k = Mid(m, c, 1) Then

continue = False

End If

c =c + 1

Loop

④

Next i

Text2.Text = result

End Sub

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