span> first1<span class="special">,</span> <span class="identifier">InputIterator1</span> last1<span class="special">,</span> 
                      <span class="identifier">InputIterator2</span> first2<span class="special">,</span> <span class="identifier">InputIterator2</span> last2<span class="special">,</span> 
                      <span class="identifier">command_queue</span> <span class="special">&amp;</span> queue <span class="special">=</span> <span class="identifier">system</span><span class="spec