<?php
$interests[2] = "music";
$interests[5] = "movie";
$interests[1] = "computer";
$interests[] = "software";

$end = end($interests);
$prev = prev($interests);

var_dump(key($interests)); 
echo "<br/>";
var_dump(current($interests));
echo "<br/>";
var_dump($end);
echo "<br/>";
var_dump($prev);
?>
