《VB程序设计》课堂例题总结(4)

If Tag=True then Print n Next n End sub

穷举法：百元买百鸡问题。假定小鸡每只5角，公鸡每只2元，母鸡每只3元。现在有100元钱要求买100只鸡，编程列出所有可能的购鸡方案。 方法一：

Private Sub Command1_Click() Dim x%, y%, z% For x= 0 to 100 For y= 0 to 100

For z= 0 to 100 step 2

If x+y+z=100 and 3*x+2*y+z*0.5=100 Then Print x,y,z End If Next z,y,x End Sub 方法二：

Private Sub Command1_Click() Dim x%, y%, z% For i = 0 To 20 For j = 0 To 33

For k = 0 To 100 Step 3

If i + j + k = 100 And i * 5 + j * 3 + k / 3 = 100 Then Print \公鸡：\母鸡：\小鸡：\ End If Next k Next j Next i End Sub

编写程序，显示所有的水仙花数（所谓水仙花数是指一个3位数，期各位数字立方和等于该数字本身，如153=1^3+5^3+3^3）。

方法一（用单循环完成，分别把三位数中的每个数字取出来） Private Sub Command1_Click() Dim i%, g%, s%, b% For i = 100 To 999 b = i \\ 100 g = i Mod 10

s = (i \\ 10) Mod 10

If b ^ 3 + g ^ 3 + s ^ 3 = i Then Print i Next End Sub

方法二（用三重循环完成，由三个数字组成三位数来判断）

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Private Sub Form_Click() Dim i%, j%, k%, s% For i = 1 To 9 For j = 0 To 9 For k = 0 To 9

If i ^ 3 + j ^ 3 + k ^ 3 = i * 100 + j * 10 + k Then Print i * 100 + j * 10 + k Next k Next j Next i End Sub

输入一个班100个学生的成绩，要求:1）求平均分2）统计高于平均分的人数 Private Sub Form_Click()

Dim a%(1 To 100)，i%, SUM%, aver!,n% For i = 1 To 100

a(i) = InputBox(\ Print a(i)

SUM = SUM + a(i) Next i

aver = SUM / 100 For i = 1 To 100

If a(i) > aver Then n = n + 1 Next i Print n End Sub

斐波那契数列,即:1,1,2,3,5,8,13……由此可知：a1=a2=1 ,an=an-1+an-2 （用数组求） Private Sub Form_Click() Dim i%,f&(30) f(1)=1:f(2)=1 Print f(1);f(2); For i=3 to 30 f(i)=f(i-2)+f(i-1) Print f(i);

If i mod 5 = 0 Then Print End If Next i End Sub

用计算机模拟掷色子游戏。一个色子有六个点数，编写程序统计掷N次（N尽量大，例如100000次）后各点子出现的次数。 方法一：

Private Sub Command1_Click() Dim c%, i&

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Dim n(1 To 6) As Single '定义一个数组记算所掷每一个色子的次数 For i = 1 To 100000

c = Int(Rnd * 6 + 1) '我们所扔的色子的点数实际是一个1~6的随机数 n(c) = n(c) + 1 '对于所要记录的这个色子对应的个数加1 Next i

For i = 1 To 6

Print \Next End Sub 方法二：

Private Sub Form_Click()

Dim dian%, i&, n1&, n2&, n3&, n4&, n5&, n6& For i = 1 To 100000 dian = Int(Rnd * 6) + 1 If dian = 1 Then n1 = n1 + 1

ElseIf dian = 2 Then n2 = n2 + 1

ElseIf dian = 3 Then n3 = n3 + 1

ElseIf dian = 4 Then n4 = n4 + 1

ElseIf dian = 5 Then n5 = n5 + 1 Else

n6 = n6 + 1 End If Next

Print n1：Print n2：Print n3：Print n4：Print n5：Print n6 End Sub

输入一串字符，分别统计各字母出现的次数，不区分字母大小写。 Private Sub Form_Click() Dim a%(65 To 90), s$

s = InputBox(\输入一串字符串：\Print \字符串为\For i = 1 To Len(s)

n = Asc(UCase(Mid(s, i, 1))) a(n) = a(n) + 1 Next

For i = 65 To 90

If a(i) <> 0 Then Print Chr(i); \的个数为:\Next End Sub

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将一个数组中的元素按逆序存放 Private Sub Form_Click() Dim i%, a%(10), t% Randomize For i = 1 To 10

a(i) = Int(Rnd * 101) + 100 Print a(i);

If i Mod 5 = 0 Then Print Next

For i = 1 To 5

t = a(i): a(i) = a(10 - i + 1): a(10 - i + 1) = t Next

Print \逆序输出结果为：\For i = 1 To 10 Print a(i);

If i Mod 5 = 0 Then Print Next End Sub

10个元素的数组求最大值。 Private Sub Form_Click() Dim i%, a%(10), max%

a(1) = Int(Rnd * 101) + 100 '先产生一个数,作为最大值的初值 max = a(1) Print a(1)

For i = 2 To 10 '紧跟着产生剩下的9个数 a(i) = Int(Rnd * 101) + 100 Print a(i)

If a(i) > max Then max = a(i)

'拿新产生的数来与最大值作比较，若比最大值大，则取代其，作为新的最大值 Next

Print \最大值为\End Sub

打印杨辉三角

Option Base 1

Private Sub Form_Click() Dim a%(7, 7)

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For i = 1 To 7 For j = 1 To i

If j = 1 Or i = j Then a(i, j) = 1 Else

a(i, j) = a(i - 1, j) + a(i - 1, j - 1) End If

Print a(i, j); Next Print Next End Sub

通过Inputbox输入5个同学的姓名和身高，显示全部同学的姓名和身高及最高的同学的姓名和身高。 Option Base 1

Private Sub Command1_Click() Dim a(5, 2), i%

a(1, 1) = Val(InputBox(\请输入第一个身高：\ a(1, 2) = InputBox(\请输入第一个姓名：\ Max = a(1, 1) maxi = 1 For i = 2 To 5

a(i, 1) = Val(InputBox(\请输入第\个身高：\ a(i, 2) = InputBox(\请输入第\个姓名：\ If a(i, 1) > Max Then Max = a(i, 1) maxi = i End If Next i

For i = 1 To 5

Print a(i, 1), a(i, 2) Next i

Print \最高的是：\身高\End Sub

数组求最大值的下标 Private Sub Form_Click() Dim i%, a%(10), maxi% a(1) = Int(Rnd * 101) + 100 maxi = 1 '记录最大值的下标 Print a(1)

For i = 2 To 10 '紧跟着产生剩下的9个数 a(i) = Int(Rnd * 101) + 100

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