class="identifier">std</span><span class="special">::</span><span class="identifier">get</span><span class="special">&lt;</span> <span class="number">1</span> <span class="special">&gt;(</span> <span class="identifier">result</span><span class="special">)</span> <span class="special">);</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"f1: GPU computation finished"</span> <span class="