How can i remove notice from my php pages

Hi everybody,
I am making my website using php now my script is running successsfully but every page it gives a notice regarding my variable how can i remove this "
Notice: Undefined index: qid in e:\inetpub\wwwroot\ ry
ew.php on line 3

Notice: Undefined index: B1 in e:\inetpub\wwwroot\ ry
ew.php on line 4

Notice: Undefined index: S1 in e:\inetpub\wwwroot\ ry
ew.php on line 5"
what is this ?Is this error or warnning?Plz help me.my code is as follows:
<?php
include(‘conn.php’);
$qid= $_POST[‘qid’];
$submit= $_POST[‘B1’];
$text=$_POST[‘S1’];
if ($submit==“Button”)

{
$ins= “update student set ans=‘$text’ where qid=$qid”;
mysql_query($ins) or
die ("Cannot insert into database ");
header(‘location: /try/no.html’);

}
?>
<HTML>
<HEAD>
<TITLE> New Document </TITLE>

</HEAD>

<BODY>
<p align=“center”>the question was<input type=“text” name=“s2” rows=“2” value =“<? echo $_REQUEST[‘quest’]; ?>” cols=“50” ></textarea></p>
<form method=“POST” action=“<?php echo $_SERVER[‘PHP_SELF’];?>”>
<input name=“qid” type=“hidden” value=“<?php echo $_REQUEST[‘qid’]; ?>” >
<p align=“center”>What is your answer?<textarea rows=“2” name=“S1” cols=“20”></textarea></p>
<p align=“center”><input type=“submit” value=“Button” name=“B1”></p>
</form>

</BODY>
</HTML>


$qid = empty($_POST['qid']) ? '' : $_POST['qid'];
$submit = empty($_POST['B1']) ? '' : $_POST['B1'];
$text = empty($_POST['S1']) ? '' : $_POST['S1'];

The above is just a short way of doing:


if(empty($_POST['qid'])){
    $qid = '';
} else {
    $qid = $_POST['qid'];
}

at the top of the parse, set the following:


error_reporting(E_PARSE);

Note: this will only allow parse errors to be shown.

You could also turn off notices in the error reporting if you have access to php.ini:

; - Show all errors, except for notices
;
error_reporting = E_ALL & ~E_NOTICE

Also you can add ‘@’ to the start of any operator to make php silent when performing the current operation. No errors, warnings, notices would be output.
I.E.:

@$qid= $_POST['qid'];

thank you markl999