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V习题解答习题二Xt2.9编写应用程序，读入一行字符，统计其中有字母、数字、空格和其它字符各有几个。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim str1, str2 As String Dim i, n, sum1, sum2, sum3, sum4 As Integer str1 = InputBox(enter a string) n = Len(str1) For i = 1 To n str2 = Mid(str1, i, 1) Select Case str2 Case a To z, A To Z sum1 = sum1 + 1 Case 0 To 9 sum2 = sum2 + 1 Case sum3 = sum3 + 1 Case Else sum4 = sum4 + 1 End Select Next MsgBox(字母 & sum1 & 数字 & sum2 & Chr(10) & 空格 & sum3 & 其它 & sum4) End SubXt2.10编写应用程序，统计并逐行显示（每行5个数）在区间10000，50000上的回文数。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim i, j, k As Integer Dim a, b, c, d, f As Integer Dim str1 As String k = 0 For i = 10000 To 50000 a = i Mod 10 b = (i Mod 100) 10 c = (i Mod 1000) 100 d = (i Mod 10000) 1000f = i 10000 If i = a * 10000 + b * 1000 + c * 100 + d * 10 + f Then str1 = str1 + Str(i) + Space(3) k = k + 1 If k Mod 5 = 0 Then str1 = str1 + Chr(10) + Chr(13) End If End If Next MsgBox(str1 + Chr(10) + Str(k)End SubXt2.15使用While语句，求两个正整数的最小公倍数。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a, b, gbs As Integer a = Val(InputBox(enter a=?) b = Val(InputBox(enter b=?) If a = b Then gbs = b Else gbs = a End If While (gbs Mod a 0) Or (gbs Mod b 0) gbs = gbs + 1 End While MsgBox(正整数 & a & 和 & b & 的最小公倍数为： & gbs) End Sub习题三Xt3.1- 0.6326531 编写求的函数过程，调用此函数求以下表达式的值。y=Function sum(ByVal n As Integer) As Integer Dim i, s As Integer s = 0 For i = 1 To n s = s + i Next sum = s End FunctionPrivate Sub Button1_Click( ) Dim y As Double y = (sum(3) + sum(4) + sum(5) / (sum(6) + sum(7) MsgBox(y= & y)End Subxt3.2 编写一个求3个数中最大值Max和最小值Min的过程。然后用这个过程分别求3个数和5个数、7个数中的最大值和最小值。 求三个数的最大值的过程 Function max(ByVal a As Integer, ByVal b As Integer, ByVal c As Integer) Dim m As Integer If a b Then m = a Else m = b End If If m c Then max = m Else max = c End If End Function 求三个数的最小值的过程 Function min(ByVal a As Integer, ByVal b As Integer, ByVal c As Integer) Dim m As Integer If a b Then m = a Else m = b End If If m m Then MsgBox(输入数据错误) End If cmn = jcf(m) / (jcf(n) * jcf(m - n) MsgBox(组合数是： & cmn)End Subxt3.5 斐波纳契（Fibonacci）数列的第一项是0，第二项是1，以后各项都是前两项的和。试用递归算法和非递归法各编写一个程序，求斐波纳契数列第N项的值. function fib1(ByVal n As Integer) 非递归算法-（递推） Dim f1, f2, f3 As Integer Dim i As Integer f1 =0 : f2 = 1 For i = 3 To n F3 = f1 + f2 第i项的值 f1 = f2 f2 = f3 Next Fib1=f3 End Sub Function fib2(ByVal n As Integer) 递归算法 If n = 1 Then fib2 = 0 If n = 2 Then fib2 = 1 If n=3 Then fib2 = fib2(n - 1) + fib2(n - 2) End Function Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim n As Integer n = Val(InputBox(n=?) MsgBox(用递推算法，数列第 & n & 项的值为 & fib1(n)MsgBox(用递归算法，数列第 & n & 项的值为 & fib2(n) End Subxt3.6 编写八进制数与十进制数相互转换的过程：（1）过程ReadOctal，读入八进制数，转换为等值的十进制数。（2）过程WriteOctal，将十进制正整数以等值的八进制形式输出。 oct_num 转int_num （8 转10） Function readoctal(ByVal oct_num As String) As Single Dim n, i, t, s As Integer s = 0 n = Len(oct_num) For i = 1 To n t = Val(Mid(oct_num, i, 1) * 8 (n - i) 各位按权位求值 s = s + t Next readoctal = s End Function int_num 转 oct_num （10 转 8） Function writeoctal(ByVal int_num As String) As Single Dim n, i, t As Integer, s As String Dim octstr(6) As String For i = 6 To 1 Step -1 octstr(i) = int_num - Int(int_num / 8) * 8 连除基数 int_num = Int(int_num / 8) Next For i = 1 To 6 s = s + (octstr(i) 逆序取余 Next writeoctal = Val(s) End Function Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a, b As Integer a = Val(TextBox1.Text) b = writeoctal(a) 调用函数过程 TextBox2.Text = Str(b) End Sub Private Sub Button2_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Dim a, b As Integer a = TextBox3.Text b = readoctal(a) 调用函数过程 TextBox4.Text = Str(b) End Subxt3.7 编写一个过程，用来计算并输出 S=1+ 的值。 Function sumd(ByVal n As Integer) As Single Dim i%, s! s = 1 : i = 1 Do i = i + 1 s = s + 1 / i Loop Until i = n sumd = s End Function Function sumf(ByVal n As Integer) As Single Dim i%, s! s = 0 For i = 1 To n s = s + 1 / i Next sumf = s End Function Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click MsgBox(sumd= & sumd(100) MsgBox(sumf= & sumf(100)End Sub-5.187378xt3.8 编写过程，用下面的公式计算的近似值： =1-+-+(-1)n-1在事件过程中调用该过程，并输出当n=100、500、1000、5000时的近似值。Function pi(ByVal n As Integer) As Single Dim i As Integer, s As Single s = 0 For i = 1 To n s = s + (-1) (i - 1) / (2 * i - 1) Next pi = 4 * s End Function Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click MsgBox(n=100,pi= & pi(100) MsgBox(n=500,pi= & pi(500) MsgBox(n=1000,pi= & pi(1000) MsgBox(n=5000,pi= & pi(5000) End Sub xt3.9 参考lt3.6 已知 sinh（x）=从键盘输入x的值，输出sinh（x）,其中：ex可用以下级数近似表示： ex1+x+= 精度为 = eps) s = s + t t = t * x / n n = n + 1 Loop jishu1 = s End Function 用通用过程实现求部分级数和 Sub jishu2(ByRef s#, ByVal x!, ByVal eps#) Dim n%, t# n = 1 : s = 0 : t = 1 Do While (Abs(t) = eps) s = s + t t = t * x / n n = n + 1 Loop End Sub 主程序调用函数过程和通用过程 Private Sub Form1_Load(ByVal sender As System.Object, _ByVal e As System.EventArgs) Handles MyBase.Load Dim f1#, f2# f1 = jishu1(2.0#, 0.000001) 调用函数过程 Call jishu2(f2, 2.0#, 0.000001) 调用通用过程 或jishu2(f2,2#,0.000001) MsgBox(f1= & Str(f1) & & f2= & Str(f2)End Sub习题四Xt4.4 从键盘输入10个整数，并放入一个一维数组，将其前5个元素与后5个元素对换，即第一个元素与第十个元素互换，第二个元素与第九个元素互换第五个元素与第六个元素互换。分别输出数组原来各元素的值和对换后各元素的值。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a(9) As Integer Dim i, t As Integer, str1 As String str1 = 原来数组： + Chr(10) + Chr(13) For i = 0 To 9a(i)=val(inputbox(“请输入a数组各元素的值”) str1 = str1 + Space(4) + Str(a(i) 输出原来数组元素 Next i str1 = str1 + Chr(10) + Chr(13) For i = 0 To 4 t = a(i) a(i) = a(9 - i) 对换数组元素 a(9 - i) = t Next i str1 = str1 + 对换后数组： + Chr(10) + Chr(13) For i = 0 To 9 str1 = str1 + Space(4) + Str(a(i) 输出对换后数组元素 Next i str1 = str1 + Chr(10) + Chr(13) MsgBox(str1) End SubXt4.5一维数组相加设有如下两组数据：A：2，8，7，6，4，28，70，25B：79，27，32，41，57，66，78，80编写一个程序，把上面两组数据分别读入两个数组。然后把两个数组中对应下标的元素相加，即2+79，8+27，25+80，并把相应的结果放入第三个数组，最后输出第三个数组的值。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a() As Integer =2,8,7,6,4,28,70,25Dim b() As Integer =79,27,32,41,57,66,78,80Dim c(7) As Integer Dim i As Integer, str1, str2, str3 As String str1 = a数组为： str2 = b数组为： str3 = c数组为： For i = 0 To 9c(i)=a(i)+b(i)str1 = str1 + Space(4) + Str(a(i) 输出a数组元素str2 = str2 + Space(4) + Str(b(i) 输出b数组元素str3 = str3 + Space(4) + Str(c(i) 输出c数组元素 Next MsgBox(str1+chr(10)+str2+chr(10)+str3) End SubXt4.6矩阵最大元素查找有一个nm的矩阵，编写程序，找出其中最大的元素所在的行和列，并输出其值及行号和列号。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a(,) As Integer Dim n,m,I,j as integer,str1 as stringDim max,row,col As Integer n=val(inputbox(“请输入矩阵行数n=”)m=val(inputbox(“请输入矩阵列数m=”) redim a(n-1,m-1) For i = 0 To n-1For j=0 to m-1 a(I,j)=val(inputbox(“请输入”&I&”行”&j&”列元素的值”)str1 = str1+ Str(a(I,j) + Space(4) 输出原来数组元素next jstr1 = str1 + Chr(10) + Chr(13) Next i Msgbox(str1) 显示输入的矩阵 Max=a(0,0) For i = 0 To n-1For j=0 to m-1If a(I,j)max thenMax=a(I,j)Row=ICol=jEnd ifnext j Next i Msgbox(“矩阵最大元素的值为：”&max&chr(10)+”它所在行号为：”&row+chr(10)+”列号为”&col) End Subxt4.7矩阵输入/输出，行/列求和，元素对换编写程序，把下面的数据输入一个二维数组： 25 36 78 13 12 26 88 93 75 18 22 32 56 44 36 58然后执行以下操作：（1）输出矩阵两个对角线上的数。（2）分别输出各行和各列的和。（3）交换第一行和第三行的位置。（4）交换第二列和第四列的位置。（5）输出处理后的数组。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a(,) As Integer = 25, 36, 78, 13, 12, 26, 88, 93, 75, 18, 22, 32, 56, 44, 36, 58 Dim rows(3), cols(3) As Integer Dim I, j, t As Integer Dim str1, str2, str3 As String str1 = str2 = 输出主,付对角线元素 For I = 0 To 3 For j = 0 To 3 If I = j Then str1 = str1 + Str(a(I, j) + Space(4) If I + j = 3 Then str2 = str2 + Str(a(I, j) + Space(4) Next j Next I MsgBox(主对角线元素： & str1 & Chr(10) & 付对角线元素： & str2) 输出各行、列的和 str1 = str2 = For I = 0 To 3 For j = 0 To 3 rows(I) = rows(I) + a(I, j) i为行循环变量， 求各行的和 cols(I) = cols(I) + a(j, I) i为列循环变量， 求各列的和 Next j str1 = str1 + Space(4) + Str(rows(I) str2 = str2 + Space(4) + Str(cols(I) Next I MsgBox(各行的和： & str1 & Chr(10) & 各列的和： & str2) 交换第一行和第三行的位置 For I = 0 To 3 i为列循环变量 t = a(0, I) a(0, I) = a(2, I) a(2, I) = t Next 交换第二列和第四列的位置 For I = 0 To 3 i为行循环变量 t = a(I, 1) a(I, 1) = a(I, 3) a(I, 3) = t Next 输出处理后的数组 For I = 0 To 3 For j = 0 To 3 str3 = str3+ Str(a(I, j) + Space(4) Next j str3 = str3 + Chr(10) Next I MsgBox(str3)End Subxt4.8编写程序，建立并输出一个1010的矩阵，该矩阵对角线元素为1，其余元素均为0。矩阵对角线Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a(9,9) As Integer Dim i, j as integer, str1 as string For i = 0 To 9For j=0 to 9If i=j or i+j=9 thena(I,j)=1Elsea(i,j)=0End ifstr1 = str1 +space(4)+str(a(i,j)next j str1 = str1 + Chr(10) + Chr(13) Next i Msgbox(str1) End Subxt4.9矩阵转置编写程序，实现矩阵转置，即将一个nm的矩阵的行和列互换。例如，a矩阵为 1 2 3 a = 4 5 6 转置后的矩阵b为 1 4 b = 2 5 3 6Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a(,) ,b(,) As Integer Dim n, m, i, j as integer, str1 as stringn=val(inputbox(“请输入矩阵行数n=”)m=val(inputbox(“请输入矩阵列数m=”) redim a(n-1,m-1)redim b(m-1,n-1)str1=”原数组为：”+chr(10) For i = 0 To n-1For j=0 to m-1a(i,j)=val(inputbox(“输入数组元素：”)str1=str1+space(4)+str(a(I,j)next j str1 = str1 + Chr(10) + Chr(13) Next i str1=str1+”转置后的数组为：”+chr(10)For i = 0 To m-1For j=0 to n-1b(i,j)=a(j,I)str1=str1+space(4)+str(b(I,j)next j str1 = str1 + Chr(10) + Chr(13) Next i Msgbox(str1) End SubXt4.10 字符串的查找与排序编写应用程序，要求在TextBox控件的文本框中输入一个英文句子后完成如下操作：(1) 分析并显示TextBox控件的Text值中含有几个字母“a”。(2) 若英文句子用“.”号结束，英文单词间用空格字符和逗号字符作为分隔字符，分析并显示TextBox控件的Text值中含有几个英文单词。(3) 把找到的单词按从小到大的次序排序后显示到另一个TextBox控件的文本框中。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim i, n, m, k, p As Integer Dim x, str1, t As String Dim a() As String x = TextBox1.Text 输入英文句子 n = Len(x) 判断英文句子的长度 For i = 1 To n If Mid(x, i, 1) = a Then 查找a字符的个数 m = m + 1 End If Next str1 = str1 + 句子中含有： & m & 个字符a & Chr(10) ReDim a(n) k = 1 For i = 1 To n a(k) = a(k) + Mid(x, i, 1) 字符连成单词 If Mid(x, i, 1) = Or Mid(x, i, 1) = , Then k = k + 1 对单词计数End If If Mid(x, i, 1) = . Then Exit For End If Next p = 1 对单词-冒泡排序 While p = 1 p = 0 For i = 1 To k - 1 If a(i) a(i + 1) Then t = a(i) a(i) = a(i + 1) a(i + 1) = t p = 1 End If Next End While For i = 1 To k 输出排序后的单词 str1 = str1 + Space(1) + a(i) If i Mod 10 = 0 Then str1 = str1 + Chr(10) End If Next MsgBox(str1) End Subxt4.11利用InputBox函数为一维数组赋值，并在输入过程中利用插入排序算法完成数组内容的排序操作。Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim a()，x As Integer Dim i, j, n as integer, str1,str2 as stringn=val(inputbox(“输入数组中数据个数”)Redim a(n-1)i=0str1=str(a(0) For i = 0 To n-1a(i)= val(inputbox(“输入第”+str(I+1)+” 个数据”)str1=str1+str(a(i)x=a(i)For j=i-1 to 0 step-1If xa(j) thena(j+1)=a(j)ElseExit forEnd ifnext j a(j+1)=xNext i For i=0 to n-1Str2=str2+str(a(i)next Msgbox(“原数组为”&chr(10)&str1&”从小到大排序后为”&chr(1