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<H2>fill, fill_n</H2>
<HR><PRE>     Algorithm</PRE><HR>
<A NAME="Summary"><H3>Summary</H3></A>
<P>Initializes a range with a given value.</P>
<H3>Contents</H3>
<UL>
<A HREF="#Synopsis"><LI>Synopsis</LI></A>
<A HREF="#Description"><LI>Description</LI></A>
<A HREF="#Complexity"><LI>Complexity</LI></A>
<A HREF="#Example"><LI>Example</LI></A>
<A HREF="#Warnings"><LI>Warnings</LI></A>
</UL>
<A NAME="Synopsis"><H3>Synopsis</H3></A>
<PRE>#include &#60;algorithm></PRE>
<PRE>
template &#60;class ForwardIterator, class T>
  void <B>fill</B>(ForwardIterator first, ForwardIterator last,
            const T&#38; value);
template &#60;class OutputIterator, class Size, class T>
  void <B>fill_n</B>(OutputIterator first, Size n, const T&#38; value);</PRE>
<A NAME="Description"><H3>Description</H3></A>
<P>The <B><I>fill</B></I> and <B><I>fill_n</B></I> algorithms are used to assign a value to the elements in a sequence.  <B><I>fill</B></I> assigns the value to all the elements designated by iterators in the range <SAMP>[first, last)</SAMP>.</P>
<P>The <B><I>fill_n</B></I> algorithm assigns the value to all the elements designated by iterators in the range <SAMP>[first, first + n)</SAMP>. <B><I>fill_n</B></I> assumes that there are at least <SAMP>n</SAMP> elements following <SAMP>first</SAMP>, unless <SAMP>first</SAMP> is an insert iterator.</P>
<A NAME="Complexity"><H3>Complexity</H3></A>
<P><B><I>fill</B></I> makes exactly <SAMP>last - first</SAMP> assignments, and <B><I>fill_n</B></I> makes exactly <SAMP>n</SAMP> assignments.</P>
<A NAME="Example"><H3>Example</H3></A>
<PRE>//
// fill.cpp
//
 #include &#60;algorithm>
 #include &#60;vector>
 #include &#60;iostream.h>
 int main()
 {
   int d1[4] = {1,2,3,4};
   //
   // Set up two vectors
   //
   vector&#60;int> v1(d1,d1 + 4), v2(d1,d1 + 4);
   //
   // Set up one empty vector
   //
   vector&#60;int> v3;
   //
   // Fill all of v1 with 9
   //
   <B>fill</B>(v1.begin(),v1.end(),9);
   //
   // Fill first 3 of v2 with 7
   //
   <B>fill_n</B>(v2.begin(),3,7);
   //
   // Use insert iterator to fill v3 with 5 11's
   //
   <B>fill_n</B>(back_inserter(v3),5,11);
   //
   // Copy all three to cout
   //
   ostream_iterator&#60;int> out(cout," ");
   copy(v1.begin(),v1.end(),out);
   cout &#60;&#60; endl;
   copy(v2.begin(),v2.end(),out);
   cout &#60;&#60; endl;
   copy(v3.begin(),v3.end(),out);
   cout &#60;&#60; endl;
   //
   // Fill cout with 3 5's
   //
   <B>fill_n</B>(ostream_iterator&#60;int>(cout," "),3,5);
   cout &#60;&#60; endl;
   return 0;
 }
Output :
9 9 9 9
7 7 7 4
11 11 11 11 11
5 5 5
</PRE>
<A NAME="Warnings"><H3>Warnings</H3></A>
<P>If your compiler does not support default template parameters then you need to always supply the <SAMP>Allocator</SAMP> template argument.  For instance you'll have to write:</P>
<PRE>vector&#60;int,allocator></PRE>
<PRE></PRE><P>instead of:</P>
<PRE>vector&#60;int></PRE>
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