Php question: Print variable names

We are developing a website in php where 2 pictures are displayed. Each time you refresh the page the pictures shuffle. The pictures are stored in an array:

$pictures = array ( '49ers.jpg', 'bears.jpg', 'bengals.jpg',
                    'bills.jpg', 'broncos.jpg',
                    'browns.jpg', 'buccaneers.jpg',
                    'cardinals.jpg', 'chargers.jpg', 'cheifs.jpg', 'colts.jpg', 'cowboys.jpg', 'dolphins.jpg', 'eagles.jpg', 'falcons.jpg', 'giants.jpg', 'jaguars.jpg', 'jets.jpg', 'lions.jpg',
'packers开发者_StackOverflow.jpg', 'panthers.jpg', 'patriots.jpg', 'raiders.jpg', 'rams.jpg', 'ravens.jpg', 'redskins.jpg', 'saints.jpg', 'seahawks.jpg', 'steelers.jpg', 'texans', 'titans.jpg', 'vikings.jpg', );

How would we write an echo/print statement to display the file names of the pictures below?

var_dump($pictures);

or

print $pictures[0] // returns 49ers.jpg

print_r($pictures);

If you are able to show to image on the page. Can't you just print the filename that you use in your html.. Assuming it's something like: <img src="images/<%= $url %>" /> -> <p><img src="images/<%= $url" /></p><p><%= $url %></p>?

<?php

$pictures = array('49ers.jpg', 'bears.jpg', 'bengals.jpg',
    'bills.jpg', 'broncos.jpg',
    'browns.jpg', 'buccaneers.jpg',
    'cardinals.jpg', 'chargers.jpg', 'cheifs.jpg', 'colts.jpg', 'cowboys.jpg', 'dolphins.jpg', 'eagles.jpg', 'falcons.jpg', 'giants.jpg', 'jaguars.jpg', 'jets.jpg', 'lions.jpg',
    'packers.jpg', 'panthers.jpg', 'patriots.jpg', 'raiders.jpg', 'rams.jpg', 'ravens.jpg', 'redskins.jpg', 'saints.jpg', 'seahawks.jpg', 'steelers.jpg', 'texans', 'titans.jpg', 'vikings.jpg');
//foreach ($pictures as $value) {
    echo '<pre>';
    print_r($pictures);

//exit;
?>