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<H2>find()</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 finds an occurrence of value in a sequence</P>
<A NAME="sec3"><H3>Synopsis</H3></A>
<PRE>#include &lt;algorithm&gt;
namespace std {
template &lt;class InputIterator, class T&gt;
InputIterator find(InputIterator start,
InputIterator finish,
const T&amp; value);
}
</PRE>
<A NAME="sec4"><H3>Description</H3></A>
<P>The <SAMP>find()</SAMP> algorithm lets you search for the first occurrence of a particular value in a sequence. <SAMP>find()</SAMP> returns the first iterator <SAMP>i</SAMP> in the range <SAMP>[start, finish)</SAMP> for which the following condition holds: </P>
<P><SAMP>*i == value. </SAMP></P>
<P>If <SAMP>find()</SAMP> does not find a match for <SAMP>value</SAMP>, it returns the iterator <SAMP>finish</SAMP>.</P>
<P>Type <SAMP>T</SAMP> must be EqualityComparable.</P>
<A NAME="sec5"><H3>Complexity</H3></A>
<P><SAMP>find()</SAMP> performs at most <SAMP>finish - start</SAMP> comparisons.</P>
<A NAME="sec6"><H3>Example</H3></A>
<UL><PRE>//
// find.cpp
//
#include &lt;vector&gt; // for vector
#include &lt;algorithm&gt; // for adjacent_find, find
#include &lt;functional&gt; // for bind1st, equal_to
#include &lt;iostream&gt; // for cout, endl
int main ()
{
// Typedef for convenience.
typedef std::vector&lt;int, std::allocator&lt;int&gt; &gt; Vector;
const Vector::value_type arr[] = { 0, 1, 2, 2, 3,
4, 2, 2, 6, 7 };
// Set up a vector.
const Vector v1 (arr, arr + sizeof arr / sizeof *arr);
// Try find.
Vector::const_iterator it = std::find (v1.begin (),
v1.end (), 3);
std::cout &lt;&lt; *it &lt;&lt; ' ';
// Try find_if.
it = std::find_if (v1.begin (), v1.end (),
std::bind1st (std::equal_to&lt;Vector::value_type&gt;(),
3));
std::cout &lt;&lt; *it &lt;&lt; ' ';
// Try both adjacent_find variants.
it = std::adjacent_find (v1.begin (), v1.end ());
std::cout &lt;&lt; *it &lt;&lt; ' ';
it = std::adjacent_find (v1.begin (), v1.end (),
std::equal_to&lt;Vector::value_type&gt;());
std::cout &lt;&lt; *it &lt;&lt; std::endl;
return 0;
}
Program Output
3 3 2 2
</PRE></UL>
<UL><PRE></PRE></UL>
<A NAME="sec7"><H3>See Also</H3></A>
<P><SAMP><A HREF="adjacent-find.html">adjacent_find()</A></SAMP>, <SAMP><A HREF="find-first-of.html">find_first_of()</A></SAMP>, <SAMP><A HREF="find-if.html">find_if()</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 25.1.2</I></P>
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