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 <H2>inplace_merge()</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>Algorithm that merges two sorted consecutive sequences into a single sorted sequence</P>
 <A NAME="sec3"><H3>Synopsis</H3></A>

 <PRE>#include &lt;algorithm&gt;

 namespace std {
   template &lt;class BidirectionalIterator&gt;
   void inplace_merge(BidirectionalIterator start,
                      BidirectionalIterator mid,
                      BidirectionalIterator finish);

   template &lt;class BidirectionalIterator, class Compare&gt;
   void inplace_merge(BidirectionalIterator start,
                      BidirectionalIterator mid,
                      BidirectionalIterator finish,
                      Compare comp);
 }
 </PRE>
 <A NAME="sec4"><H3>Description</H3></A>
 <P>The <SAMP>inplace_merge()</SAMP> algorithm merges two sorted consecutive ranges <SAMP>[start, mid)</SAMP> and <SAMP>[mid, finish)</SAMP>, and puts the result of the merge into the range <SAMP>[start, finish)</SAMP>. The merge is stable, which means that if the two ranges contain equivalent elements, the elements from the first range always precede the elements from the second. </P>
 <P>There are two versions of the <SAMP>inplace_merge()</SAMP> algorithm. The first version uses <SAMP>operator&lt;()</SAMP> as the default for comparison, and the second version accepts a third argument that specifies a binary predicate function object.</P>
 <A NAME="sec5"><H3>Complexity</H3></A>
 <P>When enough additional memory is available, <SAMP>inplace_merge()</SAMP> does at most<SAMP> (finish - start) - 1</SAMP> comparisons. If no additional memory is available, an algorithm with <SAMP>O(N * log(N))</SAMP> complexity may be used, where <SAMP>N</SAMP> is equal to <SAMP>finish - start</SAMP>.</P>
 <A NAME="sec6"><H3>Example</H3></A>

 <UL><PRE>//
 //  merge.cpp
 //

 #include &lt;algorithm&gt;    // advance, copy, inplace_merge, merge
 #include &lt;functional&gt;   // less
 #include &lt;iostream&gt;     // cout
 #include &lt;iterator&gt;     // back_inserter, ostream_iterator
 #include &lt;vector&gt;       // vector


 int main ()
 {
     typedef std::vector&lt;int, std::allocator&lt;int&gt; &gt; Vector;

     const Vector::value_type d1[] = { 1, 2, 3, 4};
     const Vector::value_type d2[] = { 11, 13, 15, 17,
                                       12, 14, 16, 18};

     // Set up two vectors.
     Vector v1 (d1 + 0, d1 + sizeof d1 / sizeof *d1);
     Vector v2 (d1 + 0, d1 + sizeof d1 / sizeof *d1);

     // Set up four destination vectors.
     Vector v3 (d2 + 0, d2 + sizeof d2 / sizeof *d2);
     Vector v4 (v3);
     Vector v5 (v3);
     Vector v6 (v3);

     // Set up one empty vector.
     Vector v7;

     // Merge v1 with v2.
     std::merge (v1.begin (), v1.end (),
                 v2.begin (), v2.end (), v3.begin ());

     // Now use comparator.
     std::merge (v1.begin (), v1.end (),
                 v2.begin (), v2.end (), v4.begin (),
                 std::less&lt;int&gt;());

     // In place merge v5.
     Vector::iterator mid = v5.begin ();
     std::advance (mid, 4);   // equivalent to mid += 4
                              // but more generic
     std::inplace_merge (v5.begin (), mid, v5.end ());

     // Now use a comparator on v6.
     mid = v6.begin ();
     std::advance (mid, 4);   // equivalent to mid += 4
                              // but more generic
     std::inplace_merge (v6.begin (), mid, v6.end (),
                         std::less&lt;int&gt;());

     // Merge v1 and v2 to empty vector using insert iterator.
     std::merge (v1.begin (), v1.end (),
                 v2.begin (), v2.end (),
                 std::back_inserter (v7));

     // Copy all to cout.
     std::ostream_iterator&lt;int, char, std::char_traits&lt;char&gt; &gt;
         out (std::cout," ");

     std::copy (v1.begin (), v1.end (), out);
     std::cout &lt;&lt; std::endl;
     std::copy (v2.begin(), v2.end (), out);
     std::cout &lt;&lt; std::endl;
     std::copy (v3.begin (), v3.end (), out);
     std::cout &lt;&lt; std::endl;
     std::copy (v4.begin (), v4.end (), out);
     std::cout &lt;&lt; std::endl;
     std::copy (v5.begin (), v5.end (), out);
     std::cout &lt;&lt; std::endl;
     std::copy (v6.begin (),v6.end (), out);
     std::cout &lt;&lt; std::endl;
     std::copy (v7.begin (), v7.end (), out);
     std::cout &lt;&lt; std::endl;

     // Merge v1 and v2 to cout.
     std::merge (v1.begin (), v1.end (),
                 v2.begin (), v2.end (), out);

     return 0;
 }


 Program Output:
 </PRE></UL>
 <UL><PRE>1 2 3 4
 1 2 3 4
 1 1 2 2 3 3 4 4
 1 1 2 2 3 3 4 4
 11 12 13 14 15 16 17 18
 11 12 13 14 15 16 17 18
 1 1 2 2 3 3 4 4
 1 1 2 2 3 3 4 4
 </PRE></UL>
 <A NAME="sec7"><H3>See Also</H3></A>
 <P><SAMP><A HREF="merge.html">merge()</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 25.3.4</I></P>

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	<A HREF="inner-product.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="inputiterators.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>inplace_merge()</H2>
	<P><B>Library:</B>  <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>Algorithm that merges two sorted consecutive sequences into a single sorted sequence</P>
	<A NAME="sec3"><H3>Synopsis</H3></A>

	<PRE>#include <algorithm>

	namespace std {
	template <class BidirectionalIterator>
	void inplace_merge(BidirectionalIterator start,
	BidirectionalIterator mid,
	BidirectionalIterator finish);

	template <class BidirectionalIterator, class Compare>
	void inplace_merge(BidirectionalIterator start,
	BidirectionalIterator mid,
	BidirectionalIterator finish,
	Compare comp);
	}
	</PRE>
	<A NAME="sec4"><H3>Description</H3></A>
	<P>The <SAMP>inplace_merge()</SAMP> algorithm merges two sorted consecutive ranges <SAMP>[start, mid)</SAMP> and <SAMP>[mid, finish)</SAMP>, and puts the result of the merge into the range <SAMP>[start, finish)</SAMP>. The merge is stable, which means that if the two ranges contain equivalent elements, the elements from the first range always precede the elements from the second. </P>
	<P>There are two versions of the <SAMP>inplace_merge()</SAMP> algorithm. The first version uses <SAMP>operator<()</SAMP> as the default for comparison, and the second version accepts a third argument that specifies a binary predicate function object.</P>
	<A NAME="sec5"><H3>Complexity</H3></A>
	<P>When enough additional memory is available, <SAMP>inplace_merge()</SAMP> does at most<SAMP> (finish - start) - 1</SAMP> comparisons. If no additional memory is available, an algorithm with <SAMP>O(N * log(N))</SAMP> complexity may be used, where <SAMP>N</SAMP> is equal to <SAMP>finish - start</SAMP>.</P>
	<A NAME="sec6"><H3>Example</H3></A>

	<UL><PRE>//
	// merge.cpp
	//

	#include <algorithm> // advance, copy, inplace_merge, merge
	#include <functional> // less
	#include <iostream> // cout
	#include <iterator> // back_inserter, ostream_iterator
	#include <vector> // vector



	int main ()
	{
	typedef std::vector<int, std::allocator<int> > Vector;

	const Vector::value_type d1[] = { 1, 2, 3, 4};
	const Vector::value_type d2[] = { 11, 13, 15, 17,
	12, 14, 16, 18};

	// Set up two vectors.
	Vector v1 (d1 + 0, d1 + sizeof d1 / sizeof *d1);
	Vector v2 (d1 + 0, d1 + sizeof d1 / sizeof *d1);

	// Set up four destination vectors.
	Vector v3 (d2 + 0, d2 + sizeof d2 / sizeof *d2);
	Vector v4 (v3);
	Vector v5 (v3);
	Vector v6 (v3);

	// Set up one empty vector.
	Vector v7;

	// Merge v1 with v2.
	std::merge (v1.begin (), v1.end (),
	v2.begin (), v2.end (), v3.begin ());

	// Now use comparator.
	std::merge (v1.begin (), v1.end (),
	v2.begin (), v2.end (), v4.begin (),
	std::less<int>());

	// In place merge v5.
	Vector::iterator mid = v5.begin ();
	std::advance (mid, 4); // equivalent to mid += 4
	// but more generic
	std::inplace_merge (v5.begin (), mid, v5.end ());

	// Now use a comparator on v6.
	mid = v6.begin ();
	std::advance (mid, 4); // equivalent to mid += 4
	// but more generic
	std::inplace_merge (v6.begin (), mid, v6.end (),
	std::less<int>());

	// Merge v1 and v2 to empty vector using insert iterator.
	std::merge (v1.begin (), v1.end (),
	v2.begin (), v2.end (),
	std::back_inserter (v7));

	// Copy all to cout.
	std::ostream_iterator<int, char, std::char_traits<char> >
	out (std::cout," ");

	std::copy (v1.begin (), v1.end (), out);
	std::cout << std::endl;
	std::copy (v2.begin(), v2.end (), out);
	std::cout << std::endl;
	std::copy (v3.begin (), v3.end (), out);
	std::cout << std::endl;
	std::copy (v4.begin (), v4.end (), out);
	std::cout << std::endl;
	std::copy (v5.begin (), v5.end (), out);
	std::cout << std::endl;
	std::copy (v6.begin (),v6.end (), out);
	std::cout << std::endl;
	std::copy (v7.begin (), v7.end (), out);
	std::cout << std::endl;

	// Merge v1 and v2 to cout.
	std::merge (v1.begin (), v1.end (),
	v2.begin (), v2.end (), out);

	return 0;
	}


	Program Output:
	</PRE></UL>
	<UL><PRE>1 2 3 4
	1 2 3 4
	1 1 2 2 3 3 4 4
	1 1 2 2 3 3 4 4
	11 12 13 14 15 16 17 18
	11 12 13 14 15 16 17 18
	1 1 2 2 3 3 4 4
	1 1 2 2 3 3 4 4
	</PRE></UL>
	<A NAME="sec7"><H3>See Also</H3></A>
	<P><SAMP><A HREF="merge.html">merge()</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 25.3.4</I></P>

	<BR>
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