Using only one array parameter with integer keys in array_merge in PHP

Description

The following code shows how to using only one array parameter with integer keys in array_merge.

Example

/*from w w w.  j a  va 2  s.  c  o  m*/
<?php
    $a=array(3=>"red",4=>"green");
    print_r(array_merge($a));
?>

The code above generates the following result.