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   4   The neatest accomplishment of the algorithms chapter is that all the
   5   work is done via iterators, not containers directly.  This means two
   6   important things:
   7 </p><div class="orderedlist"><ol type="1"><li><p>
   8           Anything that behaves like an iterator can be used in one of
   9           these algorithms.  Raw pointers make great candidates, thus
  10           built-in arrays are fine containers, as well as your own iterators.
  11         </p></li><li><p>
  12           The algorithms do not (and cannot) affect the container as a
  13           whole; only the things between the two iterator endpoints.  If
  14           you pass a range of iterators only enclosing the middle third of
  15           a container, then anything outside that range is inviolate.
  16         </p></li></ol></div><p>
  17      Even strings can be fed through the algorithms here, although the
  18      string class has specialized versions of many of these functions
  19      (for example, <code class="code">string::find()</code>).  Most of the examples
  20      on this page will use simple arrays of integers as a playground
  21      for algorithms, just to keep things simple.  The use of
  22      <span class="emphasis"><em>N</em></span> as a size in the examples is to keep
  23      things easy to read but probably won't be valid code.  You can
  24      use wrappers such as those described in the <a class="ulink" href="../23_containers/howto.html" target="_top">containers chapter</a> to
  25      keep real code readable.
  26    </p><p>
  27      The single thing that trips people up the most is the definition
  28      of <span class="emphasis"><em>range</em></span> used with iterators; the famous
  29      "past-the-end" rule that everybody loves to hate.  The
  30      <a class="ulink" href="../24_iterators/howto.html#2" target="_top">iterators
  31      chapter</a> of this document has a complete explanation of
  32      this simple rule that seems to cause so much confusion.  Once you
  33      get <span class="emphasis"><em>range</em></span> into your head (it's not that
  34      hard, honest!), then the algorithms are a cakewalk.
  35    </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="algorithms.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="algorithms.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="bk01pt09ch20.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Part IX. Algorithms </td><td width="20%" align="center"><a accesskey="h" href="../spine.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 20. Mutating</td></tr></table></div></body></html>