<div class="line"><a id="l00024" name="l00024"></a><span class="lineno">   24</span><span class="preprocessor">#include &lt;iostream&gt;</span></div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno">   25</span><span class="preprocessor">#include &lt;memory&gt;</span></div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno">   26</span><span class="preprocessor">#include &lt;functional&gt;</span></div>
<div class="line"><a id="l00027" name="l00027"></a><span class