• Multiple elements can have equivalent keys
• Elements are sorted by its key following a specific order indicated by its comparison object
• Implemented as a balanced binary search tree

#include <iostream>
#include <map>
#include <string>
 
template <class T>
void display(T it, T end)
{
	while(it != end)
	{
		std::cout<<it->first<<" "<<it->second<<std::endl;
		std::advance(it, 1);
	}
}
 
int main(int argc, char *argv[])
{
	std::multimap<std::string, std::string> m;
	m.insert(std::make_pair("Buick", "Centry"));
	m.insert(std::make_pair("Buick", "Rendezvous"));
 
	display(m.begin(), m.end());
 
	return 0;
}
			

#include <iostream>
#include <map>
#include <string>
 
template <class T>
void display(T it, T end)
{
	while(it != end)
	{
		std::cout<<it->first<<" "<<it->second<<std::endl;
		std::advance(it, 1);
	}
}
 
int main(int argc, char *argv[])
{
	std::multimap<std::string, std::string> m;
	m.insert(std::make_pair("Buick", "Centry"));
	m.insert(std::make_pair("Buick", "Rendezvous"));
	m.insert(std::make_pair("Honda", "CRV"));
	m.insert(std::make_pair("Honda", "Accord"));
 
	//equal_range
	auto ret = m.equal_range("Honda");
	for(auto it = ret.first; it != ret.second; ++it)
		std::cout<<it->second<<std::endl;
 
	return 0;
}
			

#include <iostream>
#include <map>
#include <string>
 
template <class T>
void display(T it, T end)
{
	while(it != end)
	{
		std::cout<<it->first<<" "<<it->second<<std::endl;
		std::advance(it, 1);
	}
}
 
int main(int argc, char *argv[])
{
	std::multimap<std::string, std::string> m;
	m.insert(std::make_pair("Buick", "Centry"));
	m.insert(std::make_pair("Buick", "Rendezvous"));
	m.insert(std::make_pair("Honda", "CRV"));
	m.insert(std::make_pair("Honda", "Accord"));
 
	//find
	auto it = m.find("Honda");
	std::cout<<it->first<<" "<<it->second<<std::endl;//Honda CRV
 
	//erase
	m.erase(it);
 
	display(m.begin(), m.end());
 
	return 0;
}
			

#include <iostream>
#include <map>
#include "Rectangle.h"
 
struct comp{
	bool operator()(const Rectangle &a, const Rectangle &b)
	{
		return (a.getArea() < b.getArea());
	}
};
 
template <class T>
void display(T it, T end)
{
	while(it != end)
	{
		std::cout<<it->first.getArea()<<std::endl;
		std::advance(it, 1);
	}
}
 
int main(int argc, char *argv[])
{
	std::multimap<Rectangle, int, comp> m;
	Rectangle r1(1, 2);
	Rectangle r2(1, 2);
	Rectangle r3(2, 3);
	Rectangle r4(2, 4);
 
	m.insert(std::make_pair(r1, 1));
	m.insert(std::make_pair(r2, 2));
	m.insert(std::make_pair(r3, 3));
	m.insert(std::make_pair(r4, 4));
 
	Rectangle r5(1, 2);
	auto it = m.find(r5);
	std::cout<<it->first.getArea()<<std::endl;//2
 
	display(m.begin(), m.end());
 
	return 0;
}
			

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