max_element.rst

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.. Algorithms/Querying Algorithms//max_element |90

max_element
===========

Synopsis
--------

.. parsed-literal::
    
    template<
          typename Sequence
        , typename Pred = less<_1,_2>
        >
    struct max_element
    {
        typedef |unspecified| type;
    };



Description
-----------

Returns an iterator to the largest element in ``Sequence``. 


Header
------

.. parsed-literal::
    
    #include <boost/mpl/max_element.hpp>


Parameters
----------

+---------------+-------------------------------+-----------------------------------+
| Parameter     | Requirement                   | Description                       |
+===============+===============================+===================================+
|``Sequence``   | |Forward Sequence|            | A sequence to be searched.        |
+---------------+-------------------------------+-----------------------------------+
| ``Pred``      | Binary |Lambda Expression|    | A comparison criteria.            |
+---------------+-------------------------------+-----------------------------------+


Expression semantics
--------------------


For any |Forward Sequence| ``s`` and binary |Lambda Expression| ``pred``:


.. parsed-literal::

    typedef max_element<s,pred>::type i; 

:Return type:
    |Forward Iterator|.

:Semantics:
    ``i`` is the first iterator in |begin/end<s>| such that for every iterator ``j`` 
    in |begin/end<s>|,
    
    .. parsed-literal::
         
        apply< pred, deref<i>::type, deref<j>::type >::type::value == false


Complexity
----------

Linear. Zero comparisons if ``s`` is empty, otherwise exactly ``size<s>::value - 1`` 
comparisons. 


Example
-------

.. parsed-literal::
    
    typedef vector<bool,char[50],long,double> types;
    typedef max_element<
          transform_view< types,sizeof_<_1> >
        >::type iter;
    
    BOOST_MPL_ASSERT(( is_same< deref<iter::base>::type, char[50]> ));


See also
--------

|Querying Algorithms|, |min_element|, |find_if|, |upper_bound|, |find|