 a subdivision algorithm.
                </li>
<li class="listitem">
                  With many threads it is a merging algorithm, with a small auxiliary
                  memory ( block_size * number of threads).
                </li>
</ul></div>
<p>
              This algorithm <span class="bold"><strong>eliminates the duality</strong></span>.
              The same code has <span class="bold"><strong>optimal performance</strong></span>
              with a small and a big number of threads.
           