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<P>©Copyright 1996 Rogue Wave Software</P>
<H2>multimap</H2>
<HR><PRE> Container</PRE><HR>
<A NAME="Summary"><H3>Summary</H3></A>
<P>An associative container providing access to non-key values using keys. <B><I>multimap</B></I> keys are not required to be unique. A <B><I>multimap</B></I> supports bidirectional iterators.</P>
<H3>Contents</H3>
<UL>
<A HREF="#Synopsis"><LI>Synopsis</LI></A>
<A HREF="#Description"><LI>Description</LI></A>
<A HREF="#Interface"><LI>Interface</LI></A>
<A HREF="#Constructors and Destructors"><LI>Constructors and Destructors</LI></A>
<A HREF="#Assignment Operator"><LI>Assignment Operator</LI></A>
<A HREF="#Allocator"><LI>Allocator</LI></A>
<A HREF="#Iterators"><LI>Iterators</LI></A>
<A HREF="#Member Functions"><LI>Member Functions</LI></A>
<A HREF="#Non-member Operators"><LI>Non-member Operators</LI></A>
<A HREF="#Example"><LI>Example</LI></A>
<A HREF="#Warnings"><LI>Warnings</LI></A>
<A HREF="#See Also"><LI>See Also</LI></A>
</UL>
<A NAME="Synopsis"><H3>Synopsis</H3></A>
<PRE>#include <map></PRE>
<PRE>
template <class Key, class T, class Compare = less<Key>,
class Allocator = allocator>
class <B>multimap</B> ;
</PRE>
<A NAME="Description"><H3>Description</H3></A>
<P><B><I>multimap <Key ,T, Compare, Allocator></B></I> provides fast access to stored values of type <SAMP>T </SAMP>which are indexed by keys of type <SAMP>Key</SAMP>. The default operation for key comparison is the <SAMP><</SAMP> operator. Unlike <A HREF="map_8018.htm"><B><I>map</B></I></A>, <B><I>multimap</B></I> allows insertion of duplicate keys. </P>
<P><B><I>multimap</B></I> provides bidirectional iterators which point to an instance of <SAMP>pair<const Key x, T y></SAMP> where <SAMP>x</SAMP> is the key and <SAMP>y</SAMP> is the stored value associated with that key. The definition of <B><I>multimap</B></I> provides a <SAMP>typedef</SAMP> to this pair called <SAMP>value_type</SAMP>. </P>
<P>The types used for both the template parameters <SAMP>Key</SAMP> and <SAMP>T</SAMP> must provide the following (where <SAMP>T</SAMP> is the <SAMP>type</SAMP>, <SAMP>t</SAMP> is a value of <SAMP>T</SAMP> and <SAMP>u</SAMP> is a <SAMP>const</SAMP> <SAMP>value</SAMP> of <SAMP>T</SAMP>): </P>
<PRE> Copy constructors - T(t) and T(u)
Destructor - t.~T()
Address of - &t and &u yielding T* and
const T* respectively
Assignment - t = a where a is a
(possibley const) value of T
</PRE><P>The type used for the <SAMP>Compare</SAMP> template parameter must satisfy the requirements for binary functions.</P>
<A NAME="Interface"><H3>Interface</H3></A>
<PRE>template <class Key, class T, class Compare = less<Key>,
class Allocator = allocator>
class multimap {
public:
// types
typedef Key key_type;
typedef T mapped_type;
typedef pair<const Key, T> value_type;
typedef Compare key_compare;
typedef Allocator allocator_type;
typename reference;
typename const_reference;
typename iterator;
typename const_iterator;
typename size_type;
typename difference_type;
typename reverse_iterator;
typename const_reverse_iterator;
class value_compare
: public binary_function<value_type, value_type, bool>
{
friend class multimap<Key, T, Comapare, Allocator>;
public :
bool operator() (const value_type&, const value_type&) const;
};
// Construct/Copy/Destroy
explicit multimap (const Compare& = Compare(), const Allocator& =
Allocator());
template <class InputIterator>
multimap (InputIterator, InputIterator,
const Compare& = Compare(),
const Allocator& = Allocator());
multimap (const multimap<Key, T, Compare, Allocator>&);
~multimap ();
multimap<Key, T, Compare, Allocator>& operator=
(const multimap<Key, T, Compare, Allocator>&);
// Iterators
iterator begin ();
const_iterator begin () const;
iterator end ();
const_iterator end () const;
reverse_iterator rbegin ();
const_reverse_iterator rbegin () const;
reverse_iterator rend ();
const_reverse_iterator rend () const;
// Capacity
bool empty () const;
size_type size () const;
size_type max_size () const;
// Modifiers
iterator insert (const value_type&);
iterator insert (iterator, const value_type&);
template <class InputIterator>
void insert (InputIterator, InputIterator);
iterator erase (iterator);
size_type erase (const key_type&);
iterator erase (iterator, iterator);
void swap (multimap<Key, T, Compare, Allocator>&);
// Observers
key_compare key_comp () const;
value_compare value_comp () const;
// Multimap operations
iterator find (const key_type&);
const_iterator find (const key_type&) const;
size_type count (const key_type&) const;
iterator lower_bound (const key_type&);
const_iterator lower_bound (const key_type&) const;
iterator upper_bound (const key_type&);
const_iterator upper_bound (const key_type&) const;
pair<iterator, iterator> equal_range (const key_type&);
pair<const_iterator, const_iterator>
equal_range (const key_type&) const;
};
// Non-member Operators
template <class Key, class T,class Compare, class Allocator>
bool operator== (const multimap<Key, T, Compare, Allocator>&,
const multimap<Key, T, Compare, Allocator>&);
template <class Key, class T, class Compare, class Allocator>
bool operator< (const multimap<Key, T, Compare, Allocator>&,
const multimap<Key, T, Compare, Allocator>&);
// Specialized Algorithms
template <class Key, class T, class Compare, class Allocator>
void swap (multimap<Key, T, Compare, Allocator>&,
multimap<Key, T, Compare, Allocator>&;
</PRE>
<A NAME="Constructors and Destructors"><H3>Constructors and Destructors</H3></A>
<PRE>explicit <B>multimap</B> (const Compare& comp = Compare(),
const Allocator& alloc = Allocator());</PRE>
<UL><P>Default constructor. Constructs an empty multimap that will use the optional relation <SAMP>comp</SAMP> to order keys and the allocator <SAMP>alloc</SAMP> for all storage management.</P>
</UL>
<PRE>template <class InputIterator>
<B>multimap</B> (InputIterator first,
InputIterator last,
const Compare& comp = Compare()
const Allocator& alloc = Allocator ());</PRE>
<UL><P>Constructs a multimap containing values in the range <SAMP>[first, last)</SAMP>. Creation of the new multimap is only guaranteed to succeed if the iterators <SAMP>first</SAMP> and <SAMP>last</SAMP> return values of type<SAMP> pair<class Key, class T>.</SAMP></P>
</UL>
<PRE><B>multimap</B> (const multimap<Key, T, Compare, Allocator>& x);</PRE>
<UL><P>Copy constructor. Creates a new multimap by copying all pairs of <SAMP>key</SAMP> and <SAMP>value</SAMP> from <SAMP>x</SAMP>.</P>
</UL>
<PRE><B>~multimap</B> ();</PRE>
<UL><P>The destructor. Releases any allocated memory for this multimap.</P>
</UL>
<A NAME="Assignment Operator"><H3>Assignment Operator</H3></A>
<PRE>multimap<Key, T, Compare, Allocator>&
<B>operator=</B> (const multimap<Key, T, Compare, Allocator>& x);</PRE>
<UL><P>Replaces the contents of <SAMP>*this</SAMP> with a copy of the multimap<SAMP> x</SAMP>.</P>
</UL>
<A NAME="Allocator"><H3>Allocator</H3></A>
<PRE>allocator_type <B>get_allocator </B>() const;</PRE>
<UL><P>Returns a copy of the allocator used by self for storage management.</P>
</UL>
<A NAME="Iterators"><H3>Iterators</H3></A>
<PRE>iterator <B>begin</B>() ;</PRE>
<UL><P>Returns a bidirectional <SAMP>iterator</SAMP> pointing to the first element stored in the multimap. "First" is defined by the multimap's comparison operator, <SAMP>Compare</SAMP>.</P>
</UL>
<PRE>const_iterator <B>begin</B>() const;</PRE>
<UL><P>Returns a<SAMP> const_iterator</SAMP> pointing to the first element stored in the multimap. "First" is defined by the multimap's comparison operator, <SAMP>Compare</SAMP>.</P>
</UL>
<PRE>iterator <B>end</B>() ;</PRE>
<UL><P>Returns a bidirectional <SAMP>iterator</SAMP> pointing to the last element stored in the multimap, i.e. the off-the-end value.</P>
</UL>
<PRE>const_iterator <B>end</B>() const;</PRE>
<UL><P>Returns a <SAMP>const_iterator</SAMP> pointing to the last element stored in the multimap.</P>
</UL>
<PRE>reverse_iterator <B>rbegin</B>() ;</PRE>
<UL><P>Returns a <SAMP>reverse_iterator</SAMP> pointing to the first element stored in the multimap. "First" is defined by the multimap's comparison operator, <SAMP>Compare</SAMP>.</P>
</UL>
<PRE>const_reverse_iterator <B>rbegin</B>() const;</PRE>
<UL><P>Returns a <SAMP>const_reverse_iterator</SAMP> pointing to the first element stored in the multimap.</P>
</UL>
<PRE>reverse_iterator <B>rend</B>() ;</PRE>
<UL><P>Returns a <SAMP>reverse_iterator</SAMP> pointing to the last element stored in the multimap, i.e., the off-the-end value.</P>
</UL>
<PRE>const_reverse_iterator <B>rend</B>() const;</PRE>
<UL><P>Returns a <SAMP>const_reverse_iterator</SAMP> pointing to the last element stored in the multimap.</P>
</UL>
<A NAME="Member Functions"><H3>Member Functions</H3></A>
<PRE>void
<B>clear</B> ();</PRE>
<UL><P>Erases all elements from the self.</P>
</UL>
<PRE>size_type
<B>count</B> (const key_type& x) const;</PRE>
<UL><P>Returns the number of elements in the multimap with the key value <SAMP>x</SAMP>.</P>
</UL>
<PRE>bool
<B>empty</B>() const;</PRE>
<UL><P>Returns <SAMP>true</SAMP> if the multimap is empty, <SAMP>false</SAMP> otherwise.</P>
</UL>
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