Table of postmeta row (in array) – WordPress

I need help for a little problem with my custom metabox in WordPress.

I have a table with a group of 3 values per row. Number of row is undefined, because users can add or remove one of them.

I need to save each row (so 3 values in 3 inputs) in a specific array.

For this source code, i removed voluntarily all the system which is add a row, delete a row etc… I also remove all the query/variable tests.

I think this problem isn’t difficult to solve, but i don’t see any solution..

Thanks!

function my_meta($post){ 
   $get_values = get_post_meta($post->ID,'_MY_META_ROW',false);

echo '<table>';
  foreach($get_values as $v => $MY_META_ROW){

        echo '<tr>
                <td><input type="text" name="MY_INPUT_1" value="'.$MY_META_ROW['INPUT_1'].'" /></td>
                <td><input type="text" name="MY_INPUT_2" value="'.$MY_META_ROW['INPUT_2']'" /></td>
                <td><input type="text" name="MY_INPUT_3" value="'.$MY_META_ROW['INPUT_3'].'" /></td>
            </tr>';
  }
echo '</table>';
}


add_action('save_post','save_my_inputs');
function save_my_inputs($post_id){

foreach($_POST['??????????'] as $value){

    $array_row = array (
        "MY_INPUT_1" => $POST['MY_INPUT_1'];
        "MY_INPUT_2" => $POST['MY_INPUT_2'];
        "MY_INPUT_3" => $POST['MY_INPUT_3'];
    )
  add_post_meta($post_id, '_MY_META_ROW', $value);
}
}