HTML PHP帮助表单

I'm trying my best to generate a unique link with the following information from ID1 and ID2. I've even tested with echo and paste the following .html to the server and there weren't any respond and also tried it with echo also nothing.

I need help basically , thank you.

    <form method="post" action="">

    <h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Enter ID 1:</h1>

    <input type="text" value="" name ="cid" id="cid" />

    <h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Enter ID 2:</h1>

    <input type="text" value="" name ="gid" id="gid"/>


<h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Copy Your Link     Here</h1>
<textarea style="width:500px; height:50px;"></textarea><br /><br /><br />
        <input type="submit" value="submit" name="submit" id="submit"/>

        </form>

    <?php               

$cid = $_POST["cid"];
$gid = $_POST["gid"];


        if(isset($_POST['submit'])) 
    {

        //I want to make a new link $url = "www.something.com/" together with the combination of ID 1 and ID2 .

    Example : www.something.com/ID1+ID2 // I want like this if its possible

    }
    else               
    {
        echo "You've failed";
    }

    ?>

I need help if you don't mind

<form method="post" action="">

    <h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Enter ID 1:</h1>

    <input type="text" value="" name ="cid" id="cid" />

    <h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Enter ID 2:</h1>

    <input type="text" value="" name ="gid" id="gid"/>


<h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Copy Your Link     Here</h1>
<textarea style="width:500px; height:50px;"></textarea><br /><br /><br />
        <input type="submit" value="submit" name="submit" id="submit"/>

        </form>

    <?php               




        if(isset($_POST['submit'])) 
    {
      $cid = $_POST["cid"];
     $gid = $_POST["gid"];

        //I want to make a new link $url = "www.something.com/" together with the combination of ID 1 and ID2 .

    $emp  = "Example : www.something.com/".$cid.$gid // I want like this if its possible

    }
    else               
    {
        echo "You've failed";
    }

    ?>

try this

<?php       
$new_link = ""; 
if(isset($_POST['submit'])) 
{
    if(isset($_POST['cid'],$_POST['gid']))
    {
        $cid = $_POST['cid'];
        $gid = $_POST['gid'];
        $new_link = "www.something.com/".$cid.$gid;

           // if your input is integer and you want to add them then use this
           // $new_link = "www.something.com/".($cid+$gid);

    }
}

?>


<form method="post" action="">
     <h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Enter ID 1:</h1>
        <input type="text" value="" name ="cid" id="cid" />
     <h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Enter ID 2:</h1>
        <input type="text" value="" name ="gid" id="gid"/>

    <h1 style="color:#0CF; font-family:Arial, Helvetica, sans-serif;">Copy Your Link     Here</h1>
        <textarea style="width:500px; height:50px;"><?php echo $new_link;?></textarea><br /><br /><br />

   <input type="submit" value="submit" name="submit" id="submit"/>

</form>