get the download id for the product in woocommerce

I am using woocommerce in wordpress . I have set 2 files to download for each product but when I am trying to call the both the download file link using the below code :

 $download1=$product->get_files();
[downloadable_files] => Array
        (
            [d289633f5c2d8f2f7cc9a102aea7242c] => Array
                (
                    [name] => Three Phase UPS1
                    [file] => http://localhost/creative/wp-content/uploads/woocommerce_uploads/2014/11/SolaPalm_DS.pdf
                )

            [413ff459269b8ed9e7c441eac585c035] => Array
                (
                    [name] => Three Phase UP2
                    [file] => http://localhost/creative/wp-content/uploads/woocommerce_uploads/2014/11/CFL_DS.pdf
                )

        )

I want to get the download id so that i can use the for loop to get all the donwload product link