C / C++ / MFC

<br />
bool equal(double val)<br />
{<br />
if(fabs(val) < 0.00000000001) return true;<br />
<br />
else return false;<br />
}<br />

#include <iostream>
#include <algorithm>
#include <string>
#include <vector>

using namespace std;

class Data
{
public:
	Data()
		: price_(0), years_(0)
	{
	}

	Data(int price, int years, const string& country, const string& currency)
		: price_(price), years_(years), country_(country), currency_(currency)
	{
	}

	int getPrice() { return price_; }
	int getYears() { return years_; }
	string getCurrency() { return currency_; }
	string getCountry() { return country_; }

private:
	int price_;
	string country_;
	string currency_;
	int years_;
};

template<class T>
class DataSorter
{
public:
	typedef T (Data::*Method)();

	DataSorter(Method m)
		: m_(m)
	{
	}

	bool operator()(Data& a, Data& b)
	{
		return (a.*m_)() < (b.*m_)();
	}

private:
	Method m_;
};

int main()
{
	vector<Data> v;
	v.push_back( Data(10,1,"US","US") );
	v.push_back( Data(11,2,"Australia","AUD") );
	v.push_back( Data(9,4,"France","Francs") );

	// Change the method and return type passed to the DataSorter to sort any way you choose
	sort(v.begin(),v.end(),DataSorter<string>(&Data::getCountry));
	
	for(int i = 0; i < v.size(); i++)
	{
		cout << v.at(i).getCountry()  << endl;
	}
	return 0;
}