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<H2>fill(), fill_n()</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 assigns the same value to the elements in a given range</P>
<A NAME="sec3"><H3>Synopsis</H3></A>
<PRE>#include &lt;algorithm&gt;
namespace std {
template &lt;class ForwardIterator, class T&gt;
void fill(ForwardIterator start, ForwardIterator finish,
const T&amp; value);
template &lt;class OutputIterator, class Size, class T&gt;
void fill_n(OutputIterator start, Size n, const T&amp; value);
}
</PRE>
<A NAME="sec4"><H3>Description</H3></A>
<P>The <SAMP>fill()</SAMP> and <SAMP><A HREF="fill.html">fill_n()</A></SAMP> algorithms are used to assign a value to the elements in a sequence. <SAMP>fill()</SAMP> assigns the value to all the elements designated by iterators in the range <SAMP>[start, finish)</SAMP>.</P>
<P>The <SAMP><A HREF="fill.html">fill_n()</A></SAMP> algorithm assigns the value to all the elements designated by iterators in the range <SAMP>[start, start + n)</SAMP>. <SAMP>fill_n()</SAMP> assumes that all iterators in the range <SAMP>[start, start + n)</SAMP> are dereferenceable, unless <SAMP>start</SAMP> is an insert iterator.</P>
<P>Type <SAMP>T</SAMP> must be Assignable, and <SAMP>Size</SAMP> must be convertible to an integral type.</P>
<A NAME="sec5"><H3>Complexity</H3></A>
<P><SAMP>fill()</SAMP> makes exactly <SAMP>finish - start</SAMP> assignments, and <SAMP><A HREF="fill.html">fill_n()</A></SAMP> makes exactly <SAMP>n</SAMP> assignments.</P>
<A NAME="sec6"><H3>Example</H3></A>
<UL><PRE>//
// fill.cpp
//
#include &lt;algorithm&gt;
#include &lt;iostream&gt;
#include &lt;vector&gt;
int main ()
{
// Typedef for convenience.
typedef std::vector&lt;int, std::allocator&lt;int&gt; &gt; vector;
const vector::value_type arr[] = { 1, 2, 3, 4 };
// Set up two vectors.
vector v1(arr, arr + sizeof arr / sizeof *arr);
vector v2(v1.begin (), v1.end ());
// Set up one empty vector.
vector v3;
// Fill all of v1 with 9.
std::fill(v1.begin (), v1.end (), 9);
// Fill first 3 of v2 with 7.
std::fill_n(v2.begin (), 3, 7);
// Use insert iterator to fill v3 with 5 11's.
std::fill_n(std::back_inserter (v3), 5, 11);
// Copy all three to cout.
std::ostream_iterator&lt;vector::value_type, 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;
// Fill cout with 3 5's.
std::fill_n(out, 3, 5);
std::cout &lt;&lt; std::endl;
return 0;
}
Program Output
</PRE></UL>
<UL><PRE>9 9 9 9
7 7 7 4
11 11 11 11 11
5 5 5
</PRE></UL>
<A NAME="sec7"><H3>See Also</H3></A>
<P><A HREF="algorithms.html">Algorithms</A></P>
<A NAME="sec8"><H3>Standards Conformance</H3></A>
<P><I>ISO/IEC 14882:1998 -- International Standard for Information Systems -- Programming Language C++, Section 25.2.5</I></P>
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