="lineno">   56</span>&#160;</div><div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;            <span class="keyword">virtual</span> <span class="keywordtype">void</span> Interaction(<span class="keywordtype">size_t</span> index_i, Real dt = 0.0) <span class="keyword">override</span>;</div><div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;        };</div><div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;        <span class="