<ul id="ul_id">
<li id="f_li"><a href="#">First li</a>
<ul id="f_li_ul_id">
<li id="li_ul_li1"><a href="#">First li ul li</a></li>
<li id="li_ul_li2"><a href="#">Second li ul li</a></li>
<li id="li_ul_li3"><a href="#">Third li ul li</a></li>
</ul>
</li>
<li id="s_li"><a href="#">Second li</a></li>
</ul>
I need to get f_li_ul_id from my current id li_ul_li2 and get ul_id from my current id s_li.