how to solve ajax request url in wordpress code example

Example: wordpress ajax url

<?php
add_action( 'wp_footer', 'my_ajax_without_file' );

function my_ajax_without_file() { ?>

    <script type="text/javascript" >
    jQuery(document).ready(function($) {

        ajaxurl = '<?php echo admin_url( 'admin-ajax.php' ) ?>'; // get ajaxurl

        var data = {
            'action': 'frontend_action_without_file', // your action name 
            'variable_name': "Some value" // some additional data to send
        };

        jQuery.ajax({
            url: ajaxurl, // this will point to admin-ajax.php
            type: 'POST',
            data: data,
            success: function (response) {
                console.log(response);                
            }
        });
    });
    </script> 
    <?php
}

add_action("wp_ajax_frontend_action_without_file" , "frontend_action_without_file");
add_action("wp_ajax_nopriv_frontend_action_without_file" , "frontend_action_without_file");

function frontend_action_without_file(){
    echo json_encode($_POST);
    wp_die();
}

?>