pen_list.empty())</div>
<div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160;  {</div>
<div class="line"><a name="l00062"></a><span class="lineno">   62</span>&#160;    <span class="comment">// pop current node from open list</span></div>
<div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;    <span class="keyword">auto</span> current = open_list.top();</div>
<div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;    open_list.pop();<