#include <iostream>
using namespace std;

const double LITER_TO_GALLON = .264179;
double mpg(double miles_par, double gallon_par);

int main()
{
	double miles, liters, gallons, effiency;
	char again;


	do
	{
		cout << "How many liters of gasoline has the car used?" << endl;
		cin >> liters;
		gallons = liters * LITER_TO_GALLON;
		cout << " there have been " << liters << " liters used that means there have been " << gallons << " gallons used." << endl;
		cout << "How far did the car travel?" << endl;
		cin >> miles;
		effiency = mpg(miles, gallons);
		cout << " The car traveled " << miles << " miles.";
		cout << " The car has an effiency of " << effiency << " miles per gallon." << endl;
		cout << "Do you want to make another calculation? Y = yes, N = no" << endl;
		cin >> again;
	} while ((again == 'Y') || (again == 'y'));
	cout << "Have a nice day."<< endl;
	return(0);
}

double mpg(double miles_par, double gallon_par)
{
	return(miles_par / gallon_par);
}