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 <H2>find_if()</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 a value in a sequence that satisfies a specified predicate</P>
 <A NAME="sec3"><H3>Synopsis</H3></A>

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

 namespace std {
   template &lt;class InputIterator, class Predicate&gt;
   InputIterator find_if(InputIterator start,
                         InputIterator finish,
                         Predicate pred);
 }
 </PRE>
 <A NAME="sec4"><H3>Description</H3></A>
 <P>The <SAMP>find_if()</SAMP> algorithm allows you to search for the first element in a sequence that satisfies a particular condition. The sequence is defined by iterators <SAMP>start</SAMP> and <SAMP>finish</SAMP>, while the condition is defined by the third argument: a predicate function that returns a boolean value. <SAMP>find_if()</SAMP> returns the first iterator <SAMP>i</SAMP> in the range <SAMP>[start, finish)</SAMP> for which the following condition holds:</P>
 <P><SAMP>pred(*i) == true.</SAMP></P>
 <P>If no such iterator is found, <SAMP>find_if()</SAMP> returns <SAMP>finish</SAMP>.</P>
 <A NAME="sec5"><H3>Complexity</H3></A>
 <P><SAMP>find_if()</SAMP> performs at most <SAMP>finish-start</SAMP> applications of the corresponding predicate.</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:
 </PRE></UL>
 <UL><PRE>3 3 2 2
 </PRE></UL>
 <A NAME="sec7"><H3>See Also</H3></A>
 <P><SAMP><A HREF="adjacent-find.html">adjacent_find()</A></SAMP>, <A HREF="algorithms.html">Algorithms</A>, <SAMP><A HREF="find.html">find()</A></SAMP>, <SAMP><A HREF="find-end.html">find_end()</A></SAMP>, <SAMP><A HREF="find-first-of.html">find_first_of()</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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	<TITLE>find_if()</TITLE>
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	<H2>find_if()</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 finds an occurrence of a value in a sequence that satisfies a specified predicate</P>
	<A NAME="sec3"><H3>Synopsis</H3></A>

	<PRE>#include <algorithm>

	namespace std {
	template <class InputIterator, class Predicate>
	InputIterator find_if(InputIterator start,
	InputIterator finish,
	Predicate pred);
	}
	</PRE>
	<A NAME="sec4"><H3>Description</H3></A>
	<P>The <SAMP>find_if()</SAMP> algorithm allows you to search for the first element in a sequence that satisfies a particular condition. The sequence is defined by iterators <SAMP>start</SAMP> and <SAMP>finish</SAMP>, while the condition is defined by the third argument: a predicate function that returns a boolean value. <SAMP>find_if()</SAMP> returns the first iterator <SAMP>i</SAMP> in the range <SAMP>[start, finish)</SAMP> for which the following condition holds:</P>
	<P><SAMP>pred(*i) == true.</SAMP></P>
	<P>If no such iterator is found, <SAMP>find_if()</SAMP> returns <SAMP>finish</SAMP>.</P>
	<A NAME="sec5"><H3>Complexity</H3></A>
	<P><SAMP>find_if()</SAMP> performs at most <SAMP>finish-start</SAMP> applications of the corresponding predicate.</P>
	<A NAME="sec6"><H3>Example</H3></A>

	<UL><PRE>//
	// find.cpp
	//

	#include <vector> // for vector
	#include <algorithm> // for adjacent_find, find
	#include <functional> // for bind1st, equal_to
	#include <iostream> // for cout, endl



	int main ()
	{
	// Typedef for convenience.
	typedef std::vector<int, std::allocator<int> > 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 << *it << ' ';

	// Try find_if.
	it = std::find_if (v1.begin (), v1.end (),
	std::bind1st (std::equal_to<Vector::value_type>(),
	3));

	std::cout << *it << ' ';

	// Try both adjacent_find variants.
	it = std::adjacent_find (v1.begin (), v1.end ());

	std::cout << *it << ' ';

	it = std::adjacent_find (v1.begin (), v1.end (),
	std::equal_to<Vector::value_type>());

	std::cout << *it << std::endl;

	return 0;
	}


	Program Output:
	</PRE></UL>
	<UL><PRE>3 3 2 2
	</PRE></UL>
	<A NAME="sec7"><H3>See Also</H3></A>
	<P><SAMP><A HREF="adjacent-find.html">adjacent_find()</A></SAMP>, <A HREF="algorithms.html">Algorithms</A>, <SAMP><A HREF="find.html">find()</A></SAMP>, <SAMP><A HREF="find-end.html">find_end()</A></SAMP>, <SAMP><A HREF="find-first-of.html">find_first_of()</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>

	<BR>
	<HR>
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