#include <iostream>
#include <vector>
using namespace std;

bool isRunning = true;

class Fillup {
		float amountOfGas = 0, pricePaid = 0, odometerReading = 0;
	public:
		Fillup(float a, float b, float c) { amountOfGas = a; pricePaid = b; odometerReading = c; }
		int getTravelDifference(int initialMiles) { return odometerReading - initialMiles; }
		int getAmountOfGas() { return amountOfGas; }
		int getPricePaid() { return pricePaid; }
		int getOdometer() { return odometerReading; }
		bool getInfo() {
			cout << endl << "Enter Amount Of Gas Purchased: ";
			cin >> amountOfGas;
			if(isNotValid(amountOfGas)) {
				return false;
			};
			cout << "Enter Price Paid: ";
			cin >> pricePaid;
			if(isNotValid(pricePaid)) {
				return false;
			};
			cout << "Enter Odometer Reading: ";
			cin >> odometerReading;
			if(isNotValid(odometerReading)) {
				return false;
			};
			return true;
		}
		bool isNotValid(float test) {
			if (test < 1) {
				return true;
			} else {
				return false;
			}
		}
};

class Travel {
		int initialMiles;
		vector<Fillup> fillups;
		float milesTraveled = 0, milesPerGallon = 0, pricePerGallon = 0, milesPerDollar = 0, totalAmountOfGas = 0, totalPricePaid = 0, lastOdometerRead = 0;
	public:
		Travel(float a) { initialMiles = a;}
		void addFillup(Fillup fillup) {
			fillups.push_back(fillup);
		}
		void calculateTotal() {
			milesTraveled = 0;
			totalAmountOfGas = 0;
			totalPricePaid = 0;
			for (auto & fillup : fillups) {
				milesTraveled = fillup.getTravelDifference(initialMiles);
				totalAmountOfGas = fillup.getAmountOfGas() + totalAmountOfGas;
				totalPricePaid = fillup.getPricePaid() + totalPricePaid;
			}
			milesPerGallon = milesTraveled / totalAmountOfGas;
			pricePerGallon = totalPricePaid / totalAmountOfGas;
		}
		void calculateSingle(Fillup fillup) {
			if (fillups.size() < 2 ){
				lastOdometerRead = initialMiles;
			}
			milesTraveled = fillup.getTravelDifference(lastOdometerRead);
			milesPerGallon = milesTraveled / fillup.getAmountOfGas();
			pricePerGallon = fillup.getPricePaid() / fillup.getAmountOfGas();
			lastOdometerRead = fillup.getOdometer();
		}
		void getInitialMiles() {
			cout << "Enter Initial Odometer Reading: ";
			cin >> initialMiles;
		}
		void printStats(const char* prefix = "") {
			cout << endl << prefix << "Miles Traveled: " << milesTraveled << endl;
			cout << prefix << "Miles Per Gallon: " << milesPerGallon << endl;
			cout << prefix << "Price Per Gallon: " << pricePerGallon << endl;
			if (fillups.size() > 1 ){
				cout << prefix << "Number Of Trips: " << fillups.size() << endl;
			}
		}
};

int main () {
	Travel travel (0);
	travel.getInitialMiles();
	while (isRunning) {
		Fillup fill (0,0,0);
		if (!fill.getInfo()) {
			break;
		}
		travel.addFillup(fill);
		travel.calculateSingle(fill);
		travel.printStats();
	}
	travel.calculateTotal();
	travel.printStats("Total ");
}