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It is provided "as is" without express or implied warranty. -- --><Head><Title>uninitialized_copy</Title><!-- Generated by htmldoc --></HEAD><BODY TEXT="#000000" LINK="#006600" ALINK="#003300" VLINK="#7C7F87" BGCOLOR="#FFFFFF"><A HREF="/"><IMG SRC="/images/common/sgilogo_small.gif" ALT="SGI Logo" WIDTH="80" HEIGHT="72" BORDER="0"></A><P><!--end header--><BR Clear><H1>uninitialized_copy</H1><Table CellPadding=0 CellSpacing=0 width=100%><TR><TD Align=left><Img src = "allocators.gif" Alt="" WIDTH = "194" HEIGHT = "38" ></TD><TD Align=right><Img src = "function.gif" Alt="" WIDTH = "194" HEIGHT = "38" ></TD></TR><TR><TD Align=left><Img src = "algorithms.gif" Alt="" WIDTH = "194" HEIGHT = "38" ></TD><TD Align=right></TD></TR><TR><TD Align=left VAlign=top><b>Categories</b>: allocators, algorithms</TD><TD Align=right VAlign=top><b>Component type</b>: function</TD></TR></Table><h3>Prototype</h3><pre>template <class <A href="InputIterator.html">InputIterator</A>, class <A href="ForwardIterator.html">ForwardIterator</A>>ForwardIterator uninitialized_copy(InputIterator first, InputIterator last, ForwardIterator result);</pre> <h3>Description</h3>In C++, the operator <tt>new</tt> allocates memory for an object and thencreates an object at that location by calling a constructor. Occasionally,however, it is useful to separate those two operations. <A href="#1">[1]</A> If each iteratorin the range <tt>[result, result + (last - first))</tt> points to uninitializedmemory, then <tt>uninitialized_copy</tt> creates a copy of <tt>[first, last)</tt>in that range. That is, for each iterator <tt>i</tt> in the input range,<tt>uninitialized_copy</tt> creates a copy of <tt>*i</tt> inthe location pointed to by the corresponding iterator in the output range by calling <tt><A href="construct.html">construct</A>(&*(result + (i - first)), *i)</tt>.<h3>Definition</h3>Defined in the standard header <A href="memory">memory</A>, and in the nonstandardbackward-compatibility header <A href="algo.h">algo.h</A>.<h3>Requirements on types</h3><UL><LI><tt>InputIterator</tt> is a model of <A href="InputIterator.html">Input Iterator</A>.<LI><tt>ForwardIterator</tt> is a model of <A href="ForwardIterator.html">Forward Iterator</A>.<LI><tt>ForwardIterator</tt> is mutable.<LI><tt>ForwardIterator</tt>'s value type has a constructor that takes a single argument whose type is <tt>InputIterator</tt>'s value type.</UL><h3>Preconditions</h3><UL><LI><tt>[first, last)</tt> is a valid range.<LI><tt>[result, result + (last - first))</tt> is a valid range.<LI>Each iterator in <tt>[result, result + (last - first))</tt> points to a region of uninitialized memory that is large enough to store a value of <tt>ForwardIterator</tt>'s value type.</UL><h3>Complexity</h3>Linear. Exactly <tt>last - first</tt> constructor calls.<h3>Example</h3><pre>class Int {public: Int(int x) : val(x) {} int get() { return val; }private: int val;}; int main(){ int A1[] = {1, 2, 3, 4, 5, 6, 7}; const int N = sizeof(A1) / sizeof(int); Int* A2 = (Int*) malloc(N * sizeof(Int)); uninitialized_copy(A1, A1 + N, A2);}</pre><h3>Notes</h3><P><A name="1">[1]</A>In particular, this sort of low-level memory management is usedin the implementation of some container classes.<h3>See also</h3><A href="Allocators.html">Allocators</A>, <tt><A href="construct.html">construct</A></tt>, <tt><A href="destroy.html">destroy</A></tt>, <tt><A href="uninitialized_fill.html">uninitialized_fill</A></tt>, <tt><A href="uninitialized_fill_n.html">uninitialized_fill_n</A></tt>,<tt><A href="raw_storage_iterator.html">raw_storage_iterator</A></tt><!-- start footer --><!-- Footer Begins --><STYLE TYPE="text/css"><!--TD.footer, TD.footer A{ font-family: Arial, helvetica, sans-serif; font-size: 8pt;}A.home {font-family: Arial, helvetica, sans-serif;}--></STYLE><P><A CLASS="home" HREF="index.html">STL Home</A><P><TABLE WIDTH="600" CELLPADDING="0" CELLPADDING="0" BORDER="0"> <TR> <TD ALIGN="RIGHT" CLASS="footer"><A HREF="/company_info/terms.html" TARGET="_top">terms of use</A> | <A HREF="/company_info/privacy.html" TARGET="_top">privacy policy</A></TD> <TD ALIGN="CENTER" CLASS="footer"> | </TD> <TD ALIGN="LEFT" CLASS="footer"><A HREF="/cgi-bin/feedback/" TARGET="_top">contact us</A></TD> </TR><TR> <TD ALIGN="RIGHT" CLASS="footer">Copyright © 1993-2003 Silicon Graphics, Inc. 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