erence.com/w/" href="http://en.cppreference.com/w/cpp/container/stack.html">std::stack&lt;const Taskflow*&gt;</a> stack;</div><div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;    <a class="codeRef" doxygen="/Users/twhuang/PhD/Code/cpp-taskflow/doxygen/cppreference-doxygen-web.tag.xml:http://en.cppreference.com/w/" href="http://en.cppreference.com/w/cpp/container/unordered_set.html">std::unordered_set&lt;const Taskflow*&gt;</a> visited;</div><div class="line"><a name="l00027"></a