Question

Base Class

class TransportationLink {
 protected:
    string _name;
    double _distance;

 public:
    TransportationLink(const string &name, double distance);
    const string & getName() const;
    double getDistance() const;
    void setDistance(double);

    // Passes in the departure time (as minute) and returns arrival time (as minute)
    // For example: 
    //     8 am will be passed in as 480 minutes (8 * 60)
    //     2:30 pm will be passed in as 870 minutes (14.5 * 60) 
    virtual unsigned computeArrivalTime(unsigned minute) const = 0;
};

#endif

Derived Classes

Define and implement RoadSegment.h and RoadSegment.cpp

Define a RoadSegment class that inherits from the base TransportationClass from above. This class will have a vector<double> hourlySpeeds data field which will hold the speed for all 24 hours of the day (each index is 1 hour). The vector's default speed for all hours will be passed in to the constructor. You will be able to set/change a speed for a specific hour, or all 24 speeds at once using setHourSpeed(unsigned hour, double speed) or setAllHourSpeeds(const vector<double> &) respectively.

The length of time on the road segment is calculated by taking it's distance and dividing by the speed at the time of departure. This length of time is then added to the departureTime parameter to get the arrivalTime.

Define and implement RiverSegment.h and RiverSegment.cpp

Define a RiverSegment class that inherits from the base TransportationClass from above. This class will have a vector<double> scheduledDepartureTimes data field that will keep track of the departure time (e.g. 10.5 represents the time 10:30) of all ferries on the river. You can assume these are sorted. Additionally, there is a _speed value that is the speed of the ferry at all times (ferries tend to be consistently slow). There is a setSpeed function to change the _speed value. Additionally, there is an addDepartureTime(double hour) function to add a departure time to the vector. Remember, these times need to be sorted.

Computing the arrival time for the RiverSegment is a little more complicated since you need to wait for the next available departure time. Once you find the next available departure time (after the departure time passed in), you need to add the length of time on the river segment. This is done by dividing the _distance by the _speed. Add the time on the river to the departure time (from the vector of departure times) and this will give you the arrival time.

Note: If there is no departure time scheduled for after your planned departure, you need to take the first available departure the following day. Our solution assumes the departure times are the same every day.

\*TransportationLink.cpp*\

#include "TransportationLink.h"

#include "TransportationLink.h"

#include <string>

using namespace std;

TransportationLink::TransportationLink(const string &name, double distance)
: _name(name), _distance(distance)
{}

const string & TransportationLink::getName() const {
return _name;
}

double TransportationLink::getDistance() const {
return _distance;
}

void TransportationLink::setDistance(double distance) {
_distance = distance;
}

\*main.cpp*\

#include "RoadSegment.h"
#include "RiverSegment.h"

#include <iostream>

using namespace std;

void constructRoute(vector<TransportationLink *> &);
int routeArrivalTime(const vector<TransportationLink *> &, unsigned);
void addRoad(vector<TransportationLink *> &);
void addRiver(vector<TransportationLink *> &);

int main() {

vector<TransportationLink *> route1;
constructRoute(route1);

unsigned departureTime;
unsigned arrivalTime;

cout << "Enter route departure time (in minutes): ";
cin >> departureTime;
cout << endl;

arrivalTime = routeArrivalTime(route1, departureTime);

cout << "Arrival Time: " << arrivalTime << endl;
  
return 0;
}

void constructRoute(vector<TransportationLink *> &route) {
char option = 'q';

do {
cout << endl;
cout << "Menu" << endl;
cout << "- Add Road ('D' or 'd')" << endl;
cout << "- Add River ('R' or 'r')" << endl;
cout << "- Quit ('Q' or 'q')" << endl;
cout << "Choose an action: ";
cin >> option;
cout << endl;
cin.ignore(); // get rid of whitespace character
  
if (option == 'd' || option == 'D') {
   addRoad(route);
}
else if (option == 'r' || option == 'R') {
   addRiver(route);
}
} while (option != 'q' && option != 'Q');
}

int routeArrivalTime(const vector<TransportationLink *> &route, unsigned departureTime) {
unsigned arrivalTime = departureTime;
for (unsigned i = 0; i < route.size(); ++i) {
arrivalTime = route.at(i)->computeArrivalTime(arrivalTime);
}
return arrivalTime;
}

void addRoad(vector<TransportationLink *> &route) {
string name;
double speed;
double distance;
char answer = 'n';
unsigned hour;

cout << "Enter name of road: ";
getline(cin, name);
cout << endl;
cout << "Enter road's default speed: ";
cin >> speed;
cout << endl;
cout << "Enter road's distance: ";
cin >> distance;
cout << endl;
RoadSegment *road = new RoadSegment(name, speed, distance);

cout << "Enter non-default speeds by hour (if any):" << endl;
cout << "Enter new speed? (y or n): ";
cin >> answer;
cout << endl;
while (answer != 'n' && answer != 'N') {
cout << "Which hour? (0 to 23): ";
cin >> hour;
cout << endl;
if (hour > 23) {
cout << "Invalid hour. Speed not updated." << endl;
} else {
cout << "Enter speed for hour " << hour << ": ";
cin >> speed;
cout << endl;
road->setHourSpeed(hour, speed);
}
cout << "Enter new speed? (y or n): ";
cin >> answer;
cout << endl;
}
route.push_back(road);
}

void addRiver(vector<TransportationLink *> &route) {
string name;
double speed;
double distance;
char answer = 'n';
double hour;

cout << "Enter name of river: ";
getline(cin, name);
cout << endl;
cout << "Enter river's speed: ";
cin >> speed;
cout << endl;
cout << "Enter river's distance: ";
cin >> distance;
cout << endl;
RiverSegment *river = new RiverSegment(name, speed, distance);

cout << "Enter departure times:" << endl;

do {
cout << "Enter time as an hour: (0 to 23.99): ";
cin >> hour;
cout << endl;
if (hour >= 24) {
cout << "Invalid hour. Departure time not added." << endl;
} else {
river->addDepartureTime(hour);
}
cout << "Enter new departure time? (y or n): ";
cin >> answer;
cout << endl;
} while (answer != 'n' && answer != 'N');

route.push_back(river);
}

\*TransportationLink.h*\

#include <string>

using namespace std;

#ifndef __TRANSPORTATIONLINK_H__
#define __TRANSPORTATIONLINK_H__

const int HOURS_PER_DAY = 24;
const int MINS_PER_HOUR = 60;
const int MINS_PER_DAY = MINS_PER_HOUR * HOURS_PER_DAY; //24 * 60

class TransportationLink {
protected:
string _name;
double _distance;

public:
TransportationLink(const string &, double);
const string & getName() const;
double getDistance() const;
void setDistance(double);

// Passes in the departure time (as minute) and returns arrival time (as minute)
// For example:
// 8 am will be passed in as 480 (8 * 60)
// 2:30 pm will be passed in as 870 (14.5 * 60)
virtual unsigned computeArrivalTime(unsigned minute) const = 0;
};

#endif

Answer 1