期末复习题(1)

1、编写判断一个正整数是否为“水仙花数”的函数过程。在事件过程中调用该过程，计算区间200，500上“水仙花数”的个数，并显示所有水仙花数。“水仙花数”的含义是一个数的每个数位的立方和等于该数。例153=13+53+33。结果：3Function sxhs(ByVal n As Integer) As Boolean Dim bw, gw, sw As Integer bw = n 100 sw = (n Mod 100) 10 gw = n Mod 10 If bw 3 + sw 3 + gw 3 = n Then sxhs = True Else sxhs = False End If End

2、 Function Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim m, i As Integer Dim s1 As String m = 0 For i = 200 To 500 If sxhs(i) Then s1 = s1 + Str(i) m = m + 1 End If Next MsgBox(Str(m) + vbCrLf + s1)End Sub301、编写程序，计算并输出下列数列前35项的和。 (1-2

3、-3),(4-5-6),(7-8-9), ,(3n+1)-(3n+2)-(3n+3), (注意，n=0,1,2,3)-1925Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim i, s As Integer s = 0 For i = 0 To 34 s += (3 * i + 1) - (3 * i + 2) - (3 * i + 3) Next MsgBox(s) End Sub 521.已知数据文件da5.dat中已

4、存储有20个学生一门课程的成绩（整型），编程将该文件中20个学生的成绩赋给整型数组score，然后按照从高分到低分对成绩排序，并按一行五个输出显示。Dim score(19), i, j, t As Integer Dim str1 As String = FileOpen(1, d:da5.dat, OpenMode.Input) For i = 0 To 19 Input(1, score(i) Next FileClose(1) For i = 0 To 18 For j = i + 1 To 19 If score(i) = 90) Then n = n + 1 End If tota

5、l = total + cj i = i + 1 End While If i 0 Then aver = total / i End If MsgBox(total= + CStr(total) + + aver= + CStr(aver) + + i= + CStr(i) + + n= + CStr(n) Write(2, aver, n) FileClose(1) FileClose(2)End Sub1A1. 编写程序，计算并输出下面数列前n项的和 (设n=20,结果取4位小数)。 数列为： 2/1,3/2,5/3,8/5,13/8,21/13,dim a,b, t,i,n as integerdim sum,q as si