Selected item to top in the filter search with checkboxes in php

<div class="qfltr-grp courses">
            <?php if($releated_courses) {$cor=[]; if(isset($_GET['courseid'])){$cor = explode('|',$_GET['courseid']);}
              $sorted_array=[];
              for($k=0; $k<count($releated_courses); $k++) in_array($releated_courses[$k]->subject_id,$cor)?$sorted_array[$k]= $releated_courses[$k]:'';
              for($k=0; $k<count($releated_courses); $k++) !in_array($releated_courses[$k]->subject_id,$cor)? $sorted_array[$k]= $releated_courses[$k]:'';
            $sorted_array=array_filter($sorted_array);
            foreach($sorted_array as $R){?>
              <div class="checkbox"><label><input name="qfltr-courses[]" class="qfltr-fee" value="<?=$R->subject_id?>" type="checkbox" <?php echo in_array($R->subject_id,$cor)?"checked":'';?>><?=$R->name;?></label></div>
            <?php }}else {?>
                <h6 style="text-align:center">No results</h6>
            <?php }?>