map associative container.cpp

/*NAME:Tanvi A Nimbalkar
DIV:B   ROLL NO:SECOB253*/


#include <iostream>
#include <map>
#include <string>
#include <utility> 
using namespace std;
 
int main()
{
	typedef map<string, int> mapType;
	mapType populationMap;
 
	populationMap.insert(pair<string, int>("China", 1339));
	populationMap.insert(pair<string, int>("India", 1187));
	populationMap.insert(mapType::value_type("US", 310)); 
	populationMap.insert(mapType::value_type("Indonesia", 234)); 
	populationMap.insert(make_pair("Brasil", 193)); 
	populationMap.insert(make_pair("Pakistan", 170)); 

	// Erase the end element using the erase function
	// Because it's ordered map (by key), 
	// map elements are not in the order of the entry 
	// In this map it's US since it's ordered alphabetically.
	mapType::iterator iter = --populationMap.end();
	populationMap.erase(iter);
 
	// output the size of the map
	cout << "Size of populationMap: " << populationMap.size() << '\n';
 
	for (iter = populationMap.begin(); iter != populationMap.end(); ++iter) {
		cout << iter->first <<": " 
			<< iter->second << " million\n";
	}

	// find will return an iterator to the matching element if it is found
	// or to the end of the map if the key is not found
	string country("Indonesia");
	iter = populationMap.find(country);
	if( iter != populationMap.end() ) 
		cout << country <<"'s populations is "
			<< iter->second << " million\n";
	else
		cout << "Key is not in populationMap" << '\n';
 
	// clear the entries in the map
	populationMap.clear();
}