Displaying PHP array in a custom format

Lets say I have an array like this:

$Array = array(1, 5, 7, 11, 16, 20);

I would like to get this result:

1 - - - 5 - 7 - - - 11 - - - - 16 - - - 20

Basically I’d like to get a "-" for non-existent values in the array.
How can I achieve this outcome?
Thanks for your help.

>Solution :

You can loop through all the numbers you’re interested in and check whether they are in your array:

<pre>
    <?php
        $array = [1, 5, 7, 11, 16, 20];

        for($i = 1; $i <= end($array); $i++) {
            if(in_array($i, $array))
                print $i . ($i==end($array) ? "" : " ");
            else
                echo "- ";
        };
    ?>
</pre>