Aggregate data in PHP

form.html

<form action="process.php" method="post">
<textarea name="myinput" id="myinput" cols="12" rows="6"></textarea>
<input type="submit" value="send">
</form>

process.php

<?php
/* This code takes input like this:
aaf341:40
bb33bs:10
98jjnw:10
000000:20
aaf341:40

and outputs this

aaf341:80
bb33bs:10
98jjnw:10
000000:20
*/
$data = explode("\n", $_POST['myinput']);
$group = array();
foreach($data as $item) {
        // explode into key -> value
        $kv = explode(":",$item);
        if(array_key_exists($kv[0], $group)) {
                // If the key item already exists add it
                $group[$kv[0]] += floatval($kv[1]);
        } else {
                $group[$kv[0]] = floatval($kv[1]);
        }
}
foreach($group as $product => $totals) {
        echo $product.":".$totals."<br>";
}
?>