向各位高手请教一下，这两题算法分析题该怎么解。。。?

两题算法分析题求指教，空格该怎么填啊~~~~~~最好有解题思路~~~~~谢谢！！！

1．下面程序的功能是统计文件file2.txt中数字符号出现的次数。
程序的思想是：每次从文件中读取一个字符，判断是否是数字字符。若是数字字符，计数器加1。
    Private Sub Button1_Click(…) Handles Button1.Click
    Dim a As Integer, c As Char
       __________(3, "file2.txt" , OpenMode.Input)          FileOpen
    a = 0
    Do While Not EOF(3)
        c = InputString( 3 ，1 )      ' 读取一个字符，
        If ___________ Then         c >= "0" And c <= "9"
         a= ____________              ' 计数器加1    a+1
        End If
    Loop
    FileClose (3)
    TextBox1.Text= " 数字字符出现的次数:" & a
    End Sub

2．求n的阶乘。类Fac用于求n的阶乘，类Form1中Button1_Click事件过程利用了类Fac求5的阶乘。
Public Class Form1
Inherits System.Windows.Forms.Form
Private Sub Button1_Click(……) Handles Button1.Click
Dim a as New Fac(5)
  ______________ CalFac()
a.Display()
End Sub
End Class
Class Fac
Private n, f As Integer
Public Sub New(ByVal n1 As Integer)
n = n1
f = 1
End Sub
Public Sub CalFac()
Dim k As Integer = n
Do While k > 1
f = f * k
 __________   k=k-1
Loop
End Sub
sub display()
    debug.writeline(n & "!="  & f)
  ___________   End Sub
End Class

[ 本帖最后由 asd111zzz 于 2010-5-24 16:08 编辑 ]