WHAT THE HURR? This "Multiplication Tutor" assignment for school is killing me. Help

johnnydr87

Ok, this should be a simple assignment for my WebApps class which I just started this semester. I would really appreciate it if someone helped (a veteran would blaze through this in no time).

What the program is supposed to do is very simple:
-Generate two random variables between 0 and 12.
-Show the User a mathematical multiplication problem with the two variables, and ask them for the answer.
-if they get it right, tell them good job, if not, show them the correct answer.
-one php file

I have poured over and over my code, but I always get the "sorry, incorrect answer" page with NEW randomly generated numbers (different than the variable values than the previous page). I have tried hidden values in forms, but that didn't work. Here is the code please tell me where I went wrong:

<?
echo "<title>Multiplication Tutor by John Richter</title><h1><center>Multiplication

Tutor</center></h1>";

if ($ans=="")
{
$var1=rand(0,12);
$var2=rand(0,12);
echo "<font size=5><center>Let's see how good you are at multiplication. <br>
What's $var1 x $var2?<br>";
echo "<form action=\"$PHP_SELF\" method=post> <input type=text name=ans size=5>
<input type=submit value=\"--->\"></center></font>";
}
else
{
if ($ans==($var1*$var2))
{

echo "<center<h1>>GREAT!!!</h1>
<br><br><a href=\"http://electrontrap.com/assignment77.php\"><h2>Try Another

One!</h2></a></center>";
}
else
{

echo "<center><h1>Sorry. $var1 x $var2 = ",$var1*$var2;
echo "<br><br><a href=\"http://electrontrap.com/assignment77.php\"><h2>Try Another

One!</h2></a></center>";
}
}
?>

rehfeld

your problem is you are not storing the values of the random vars

so when they submit an answer, you have nothing to check thier answer against.

you could store the values in hidden form fields. then use those to check if thier answer was right when they resubmit the form.

TheDefender

On a side note, I realize your code's grade is probably graded harder on making the multiplication part work, but you may want to look in the manual at predefined variables and the use of the superglobal arrays ($GET, $POST, $_SERVER, etc.) and register global settings. (On my server, your code would fail, simply because your code is based on the assumption that register globals is on, and it's off on my server). Better to learn good coding habits early on. You also want to build in some basic error checking to make sure the variable is set, that it's not blank and that it is numeric.

To elaborate on rehfeld's and my comments, try something like this:

<?php
if(isset($_POST['ans']) && ($_POST['ans'] != "" && is_numeric($_POST['ans']))){	
	$varsub1 = $_POST['varsub1'];
	$varsub2 = $_POST['varsub2'];
	$ans = $_POST['ans'];
	$rightans = ($varsub1*$varsub2);
	echo "Your guess: ".$varsub1."x".$varsub2."=".$ans."<br />";
	echo "Right answer: ".$varsub1."x".$varsub2."=".$rightans."<br />";
	if($ans == $rightans){
		echo "<font style=\"color: #00FF00;\">You got it right!</font>";
	} else {
		echo "<font style=\"color: #FF0000;\">Sorry, you got it wrong.</font>";
	}

} elseif(isset($_POST['ans']) && ($_POST['ans'] == "" || !is_numeric($_POST['ans']))){
		echo "You must insert a numeric guess for me to check it.";		
}

echo "<br /><br />";
$var1=rand(0,12); 
$var2=rand(0,12); 
echo "What's ".$var1." x ".$var2."?<br />"; 
?>

<form action="<?php echo $_SERVER['PHP_SELF']?>" method="post">
<input type="text" name="ans" size="5">
<input type="hidden" name="varsub1" value="<?php echo $var1; ?>">
<input type="hidden" name="varsub2" value="<?php echo $var2; ?>">
<input type=submit value="--->">

Roger_Ramjet

Bette to learn good coding habits early on.

To take The Defender's comments one stage further: If I was marking your assignment then you would fail anyway, even if it worked. It is not structured code.

I know that you just started this semester, but they should have begun by teaching you basic good coding practice, and the only way to make that stick is to penalise you severly when you don't do it right. Think of it like using a machine dangerously in 'shop'. Were your code fully structured and commented, with it's logic made explicit, then you would have realised the problem yourself.

Don't take this amiss, I know it's your teachers fault. But by the time you finish your education and try to get a job in this field you will need to have the habit. You see, by then, professionals like me will have reclaimed the ground overrun by amatuers during the dot com revolution. So pass these links on to your teachers as well as reading them yourself.

The web is in a phase of massive and rapid consolidation. And the survivors are the ones built or run by thoroughly seasoned pros. When you apply for a job, they'll ask to see a portfolio, and they won't look at it in a browser, they'll look at your source code in a text editor. What works when you are on your own just does not cut it on a large project team. Apart from that, XML etc are going to force you to write well-structured code; and it will all be XML in a couple of years.

So I did a Google for you and here are some links that will explain what I'm talking aboput and why it is so important.

http://www.macromedia.com/v1/handlers/index.cfm?id=17556&method=full
http://www.ordersomewherechaos.com/rosso/webdev/structured_code/
http://director-online.com/buildArticle.php?id=158

TheDefender

:o {Going down shame spiral for disregarding deprecated HTML tags and using the <font> tag in my example more than once...} LOL I hope my code wouldn't have failed you Roger. 😉

Roger_Ramjet

If you handed in that code for an assignment: it would not have got a distinction. As part of a job application: well, we would have interviewed you. Reviewing it for quality control: I'd chuck it back after one look.

johnnydr87

uhm...thanks? .....

yeah....thanks.....

Anyways, not really planning on majoring in comp sci, but improving my code doesn't hurt anyhow.