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  <li><a href="#assign-by-value-and-aliasing" id="toc-assign-by-value-and-aliasing" class="nav-link" data-scroll-target="#assign-by-value-and-aliasing">Assign-by-value and aliasing</a></li>
  </ul></li>
  <li><a href="#multiple-indexes-with-vectors-and-matrices" id="toc-multiple-indexes-with-vectors-and-matrices" class="nav-link" data-scroll-target="#multiple-indexes-with-vectors-and-matrices">Multiple indexes with vectors and matrices</a>
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  <li><a href="#vect