blob: 75b03ccba5e75eccdb5853552832b2a7d3f58ca8 [file] [log] [blame]
<HTML>
<HEAD>
<TITLE>reverse_copy()</TITLE>
<LINK REL=StyleSheet HREF="../rw.css" TYPE="text/css" TITLE="Apache stdcxx Stylesheet"></HEAD>
<BODY BGCOLOR=#FFFFFF>
<A HREF="reverse.html"><IMG SRC="images/bprev.gif" WIDTH=20 HEIGHT=21 ALT="Previous file" BORDER=O></A><A HREF="noframes.html"><IMG SRC="images/btop.gif" WIDTH=56 HEIGHT=21 ALT="Top of Document" BORDER=O></A><A HREF="booktoc.html"><IMG SRC="images/btoc.gif" WIDTH=56 HEIGHT=21 ALT="Contents" BORDER=O></A><A HREF="tindex.html"><IMG SRC="images/bindex.gif" WIDTH=56 HEIGHT=21 ALT="Index page" BORDER=O></A><A HREF="reverse-iterator.html"><IMG SRC="images/bnext.gif" WIDTH=25 HEIGHT=21 ALT="Next file" BORDER=O></A><DIV CLASS="DOCUMENTNAME"><B>Apache C++ Standard Library Reference Guide</B></DIV>
<H2>reverse_copy()</H2>
<P><B>Library:</B>&nbsp;&nbsp;<A HREF="2-9.html">Algorithms</A></P>
<PRE><HR><B><I>Function</I></B><HR></PRE>
<UL>
<LI><A HREF="#sec1">Local Index</A></LI>
<LI><A HREF="#sec2">Summary</A></LI>
<LI><A HREF="#sec3">Synopsis</A></LI>
<LI><A HREF="#sec4">Description</A></LI>
<LI><A HREF="#sec5">Complexity</A></LI>
<LI><A HREF="#sec6">Example</A></LI>
<LI><A HREF="#sec7">See Also</A></LI>
<LI><A HREF="#sec8">Standards Conformance</A></LI>
</UL>
<A NAME="sec1"><H3>Local Index</H3></A>
No Entries
<A NAME="sec2"><H3>Summary</H3></A>
<P>An algorithm that reverses the order of elements in a sequence while copying them to a new sequence</P>
<A NAME="sec3"><H3>Synopsis</H3></A>
<PRE>#include &lt;algorithm&gt;
namespace std {
template &lt;class BidirectionalIterator, class OutputIterator&gt;
OutputIterator reverse_copy(BidirectionalIterator start,
BidirectionalIterator finish,
OutputIterator result);
}
</PRE>
<A NAME="sec4"><H3>Description</H3></A>
<P>The <SAMP>reverse_copy()</SAMP> algorithm copies the range <SAMP>[start, finish)</SAMP> to the range <SAMP>[result, result + (finish - start))</SAMP> such that for any nonnegative integer<SAMP> i &lt; (finish - start)</SAMP>, the following assignment takes place:</P>
<P><SAMP>*(result + (finish - start) - i) = *(start + i)</SAMP></P>
<P><SAMP>reverse_copy()</SAMP> returns<SAMP> result + (finish - start)</SAMP>. The ranges <SAMP>[start, finish)</SAMP> and <SAMP>[result, result + (finish - start))</SAMP> must not overlap. </P>
<A NAME="sec5"><H3>Complexity</H3></A>
<P><SAMP>reverse_copy()</SAMP> performs exactly <SAMP>(finish - start)</SAMP> assignments.</P>
<A NAME="sec6"><H3>Example</H3></A>
<UL><PRE>//
// reverse.cpp
//
#include &lt;algorithm&gt; // for reverse, reverse_copy
#include &lt;vector&gt; // for vector
#include &lt;iostream&gt; // for cout, endl
#include &lt;iterator&gt; // for ostream_iterator
int main ()
{
typedef std::vector&lt;int, std::allocator&lt;int&gt; &gt; Vector;
typedef std::ostream_iterator&lt;int, char,
std::char_traits&lt;char&gt; &gt;
Iter;
// Initialize a vector with an array of integers.
const Vector::value_type a[] = { 1, 2, 3, 4, 5,
6, 7, 8, 9, 10 };
Vector v (a + 0, a + sizeof a / sizeof *a);
// Print out elements in original (sorted) order.
std::cout &lt;&lt; "Elements before reverse: \n ";
std::copy (v.begin (), v.end (), Iter (std::cout, " "));
// Reverse the ordering.
std::reverse (v.begin (), v.end ());
// Print out the reversed elements.
std::cout &lt;&lt; "\n\nElements after reverse: \n ";
std::copy (v.begin (), v.end (), Iter (std::cout, " "));
std::cout &lt;&lt; "\n\nA reverse_copy to cout: \n ";
std::reverse_copy (v.begin (), v.end (),
Iter (std::cout, " "));
std::cout &lt;&lt; std::endl;
return 0;
}
Program Output:
</PRE></UL>
<UL><PRE>Elements before reverse:
1 2 3 4 5 6 7 8 9 10
Elements after reverse:
10 9 8 7 6 5 4 3 2 1
A reverse_copy to cout:
1 2 3 4 5 6 7 8 9 10
</PRE></UL>
<A NAME="sec7"><H3>See Also</H3></A>
<P><SAMP><A HREF="reverse.html">reverse()</A></SAMP></P>
<A NAME="sec8"><H3>Standards Conformance</H3></A>
<P><I>ISO/IEC 14882:1998 -- International Standard for Information Systems -- Programming Language C++, Section 25.2.9</I></P>
<BR>
<HR>
<A HREF="reverse.html"><IMG SRC="images/bprev.gif" WIDTH=20 HEIGHT=21 ALT="Previous file" BORDER=O></A><A HREF="noframes.html"><IMG SRC="images/btop.gif" WIDTH=56 HEIGHT=21 ALT="Top of Document" BORDER=O></A><A HREF="booktoc.html"><IMG SRC="images/btoc.gif" WIDTH=56 HEIGHT=21 ALT="Contents" BORDER=O></A><A HREF="tindex.html"><IMG SRC="images/bindex.gif" WIDTH=56 HEIGHT=21 ALT="Index page" BORDER=O></A><A HREF="reverse-iterator.html"><IMG SRC="images/bnext.gif" WIDTH=20 HEIGHT=21 ALT="Next file" BORDER=O></A>
<!-- Google Analytics tracking code -->
<script src="http://www.google-analytics.com/urchin.js" type="text/javascript">
</script>
<script type="text/javascript">
_uacct = "UA-1775151-1";
urchinTracker();
</script>
<!-- end of Google Analytics tracking code -->
</BODY>
</HTML>