下面程序的功能是把文件file11.txt中重复字符去掉后(即若有多个字符相同,则只保留1个)写入文件file2.txt。请填空。 Private Sub Command1__Click() Dim inchar AS String,temp AS String,outchar AS String utchar=” ” pen=”file1.txt” For Input AS #1 pen=”file2.txt” For Output AS ______ n=LOF( ______ ) inchar=Input$(n,1) For k=1 To n temp=Mid(inchar,k,1) If InStr(outchar,temp)= ______ Then outchar=outchar & temp End If Next k print #2, ______ close #2 close #1 End Sub