<大学程序设计基础-Visual Basic>教材课后习题答案第1章一、选择题1 2 3 4 5 6 7B D BC B B D第2章一、选择题1 2 3 4 5 6 7 8 9 10B C B C B C A A A A11 12 13 14A B A A二、填空题1.rem或’ _ ：2.“” # #3.5x2-3x-2sinA/34.3214565.300三、操作题1、程序段：Private Sub Command1_Click()Dim x As Integer, y As IntegerDim s As Long, c As Longx = Text1.Texty = Text2.Texts = x * yc = (x + y) * 2Label3.Caption = "长方形的面积为" + Str(s)Label4.Caption = "长方形的周长为" + Str(c)End Sub3、程序段：Private Sub Command1_Click()Text1.Text = "第一"End SubPrivate Sub Command2_Click()Text1.Text = "第二"End Sub4、程序代码：Private Sub Text1_Change()Text1.MaxLength = 10End Sub5、程序代码：Private Sub Text1_Click()Text1.SelStart = 0Text1.SelLength = Len(Text1.Text)End Sub第3章一、选择题1 2 3 4 5 6 7D A D B A D B二、填空题1. False2.B^2-4*a*c else三、操作题1．从键盘输入三个值，判断它们能否构成三角形的三个边。
如果能构成一个三角形，则计算三角形的面积。
Dim a As Integer, b As Long, c As Long, s As Single, p As Singlea = Val(InputBox("请输入一个值："))b = Val(InputBox("请输入一个值："))c = Val(InputBox("请输入一个值："))If (a + b > c And a + c > b And b + c > a) Thenp = (a + b + c) / 2s = Sqr(p * (p - a) * (p - b) * (p - c))Print a & "," & b & "," & c & "能构成一个三角形,它的面积为:" & sEnd If2．编写程序，任意输入一个整数，判定该整数奇偶性。
Dim n As Integern = Val(InputBox("请输入一个整数："))If n Mod 2 = 0 ThenPrint n & "是偶数"ElsePrint n & "是奇数"End If3．求一元二次方程的a*x^2+b*x+c=0的根。
Dim a As Integer, b As Integer, c As Integer, delta As Single, x1 As Single, x2 As Singlea = Val(InputBox("请输入一个整数："))b = Val(InputBox("请输入一个整数："))c = Val(InputBox("请输入一个整数："))delta = b ^ 2 - 4 * a * cIf delta = 0 Thenx1 = -b / (2 * a)Print "一元二次方程有两个相等的实根x1=x2=" & x1ElseIf delta > 0 Thenx1 = (-b + Sqr(delta)) / (2 * a)x2 = (-b - Sqr(delta)) / (2 * a)Print "一元二次方程有两个不等的实根x1=" & x1 & ",x2=" & x2Elsex1 = (-b) / (2 * a)x2 = Sqr(-delta) / (2 * a)Print "一元二次方程有两个不等的虚根x1=" & x1 & "+" & x2 & "i,x2=" & x1 & "-" & x2 & "i"End IfEnd If4. 任意输入三个数，输出最大数。
Dim a As Integer, b As Integer, c As Integer, max As Integera = Val(InputBox("请输入一个整数："))b = Val(InputBox("请输入一个整数："))c = Val(InputBox("请输入一个整数："))max = aIf max < b Thenmax = bEnd IfIf max < c Thenmax = cEnd IfPrint "最大数是" & max5．任意输入三个数，由大到小排序输出。
Dim a As Integer, b As Integer, c As Integer, temp As Integera = Val(InputBox("请输入一个整数："))b = Val(InputBox("请输入一个整数："))c = Val(InputBox("请输入一个整数："))If a < b Thentemp = aa = bb = tempEnd IfIf b > c ThenPrint a, b, cElseIf a > c ThenPrint a, c, bElsePrint c, a, bEnd IfEnd If第4章一、选择题1 2 3 4 5 6 7 8 9 10A B A C D B A D B B11 12 13 14 15 16D C D C B B二、填空题1. 92. 1 2 33. 74. 100+100；x mod 5=05. 66. 57. * 2 515 30 7516 32 80三、编程题1．键盘输入几个不同的数，将它们从大到小排序。
2．设计程序，求出S=11+（1+2）+（1+2+3）+…+（1+2+3+4+…+N）的值。
Dim i As Integer, sn As Long, s As Long, n As Integersn = 0s = 0n = InputBox("")For i = 1 To nsn = sn + is = s + snNextPrint s运行结果：若n为10，S为220。
3．输入X的值，求S=x-x^3/3!+x^5/5!- …的前20项的和值。
Dim x As Single, i As Integer, s As Doublex = InputBox("输入X值：")s = xFor i = 1 To 19p = 1For j = 1 To 2 * i + 1p = p * jNexts = s + (-1) ^ (i) * x ^ (2 * i + 1) / pNextPrint s运行结果：当X为2时，S为0.91(精确到小数点后两位)4．勾股定理中3个数的关系是：a2+b2=c2。
编写程序，输出30以内满足上述关系的整数组合，例如3、4、5就是一个整数组合。
Dim a As Integer, b As Integer, c As Integer, k As IntegerFor a = 1 To 30For b = 1 To 30For c = 1 To 30If a ^ 2 + b ^ 2 = c ^ 2 Then k = k + 1: Print a, b, cNextNextNextPrint k运行结果：225．输出1000以内的完全数。
完全数就是它的各个约数之和等于该数本身（如：6=1+2+3，6是完全数）。
Dim i As Integer, j As Integer, a As IntegerFor i = 2 To 1000a = 0For j = 1 To i - 1If i Mod j = 0 Then a = a + j '判断j是否能整除i，如果能，则a增加j Next jIf a = i Then Print i '判断i是否是完全数，如果是，则输出iNext i运行结果：6284966．编程求出所有的水仙花数。
水仙花数就是一个三位数，其各位数字立方和等于该数。
（如153=13+53+33）。
Dim i As Integer, s As IntegerDim a As Integer, b As Integer, c As IntegerPrint "100到999所有水仙花数：";For i = 100 To 999a = i \ 100 '取百位数b = i \ 10 Mod 10 '或 b = i Mod 100 \10 取十位数c = i Mod 10 '取个位数s = a ^ 3 + b ^ 3 + c ^ 3 '水仙花数的判断依据If s = i Then Print i;Next i运行结果：100到999所有水仙花数：153 370 371 4077．编写程序，输出100～300间的所有素数。
Dim i As Integer, j As Integer, c As Integer, k As IntegerFor i = 100 To 300For j = 2 To i - 1If i Mod j = 0 Then Exit ForNextIf i = j ThenPrint i;k = k + 1s = s + iIf k Mod 10 = 0 Then PrintEnd IfNextPrintPrint "100～300间总共有" + Str(k) + "个素数，" + "和值为" + Str(s)运行结果：8．我国现有人口为13亿。