Question textFor this programming question, you will be working with Polymorphism. Given the base abstract class "airplane", the derived classes "passenger" and "cargo", and the container class "airport" (defined in airport.h): #ifndef AIRPORT_H#define AIRPORT_H #include "airplane.h"#include "passenger.h"#include "cargo.h" #include #include using namespace std; class airport{private: string city; string code; vector airplanes; public: airport(const string &_city, const string &_code); airport(const airport &RHS); airport &operator=(const airport &RHS); ~airport(); void add_airplane(const airplane &plane); void summary() const; void list_airplanes() const;}; #endif Modify the base class airplane and the derived classes passenger and cargo (following the comments in the provided template files), and write the implementation of the member functions summary and list_airplanes. Here is the implementation of the other member functions of the "airport" class: airport::airport(const string &_city, const string &_code){ city = _city; code = _code;} airport::airport(const airport &RHS){ city = RHS.city; code = RHS.code; for (airplane *plane : RHS.airplanes) { if (plane != nullptr) { airplane *temp_plane; if (plane-get_type() == 'P') { temp_plane = new passenger(*((passenger *)plane)); } else { temp_plane = new cargo(*((cargo *)plane)); } airplanes.push_back(temp_plane); } }} airport &airport::operator=(const airport &RHS){ if (this != &RHS) { city = RHS.city; code = RHS.code; if (airplanes.size() 0) // Delete allocated memory { for (int i = airplanes.size() - 1; i = 0; i--) { if (airplanes.at(i) != nullptr) { delete airplanes.at(i); airplanes.pop_back(); } } } for (airplane *plane : RHS.airplanes) { if (plane != nullptr) { airplane *temp_plane; if (plane-get_type() == 'P') { temp_plane = new passenger(*((passenger *)plane)); } else { temp_plane = new cargo(*((cargo *)plane)); } airplanes.push_back(temp_plane); } } } return *this;} airport::~airport(){ if (airplanes.size() 0) // Delete allocated memory { for (int i = airplanes.size() - 1; i = 0; i--) { if (airplanes.at(i) != nullptr) { delete airplanes.at(i); airplanes.pop_back(); } } }} void airport::add_airplane(const airplane &plane){ airplane *temp_plane; if (plane.get_type() == 'P') { temp_plane = new passenger((const passenger &)plane); } else { temp_plane = new cargo((const cargo &)plane); } airplanes.push_back(temp_plane);} HINT: You can use the code from these functions when writing the solution for the requested member functions. NOTES: You can safely assume that the input is always correct. You must use function identifiers based on the specifications of the question when writing your solution. You do not need to write a main function. Solutions that do not compile will receive a 100 % penalty. Hardcoding the output will translate into a 100 % penalty. Answer:(penalty regime: 0 %)// In airport.cpp #include "airport.h" #include using namespace std; void airport::summary() const { The program initializes two counters to track passenger and cargo aircraft numbers at zero. The program checks Code for airplane.h 1234567891011121314151617181920212223242526272829// airplane.h#ifndef AIRPLANE_H#define AIRPLANE_H#include #include using namespace std;class airplane {private: string manufacturer; string model; string tail_number;public: airplane(const string& _manufacturer, const string& _model, const string& _tail_number) : manufacturer(_manufacturer), model(_model), tail_number(_tail_number) {} virtual char get_type() const = 0; virtual void print() const { cout

Question

Question textFor this programming question, you will be working with Polymorphism. Given the base abstract class "airplane", the derived classes "passenger" and "cargo", and the container class "airport" (defined in airport.h): #ifndef AIRPORT_H#define AIRPORT_H #include "airplane.h"#include "passenger.h"#include "cargo.h" #include #include using namespace std; class airport{private: string city; string code; vector airplanes; public: airport(const string &_city, const string &_code); airport(const airport &RHS); airport &operator=(const airport &RHS); ~airport(); void add_airplane(const airplane &plane); void summary() const; void list_airplanes() const;}; #endif Modify the base class airplane and the derived classes passenger and cargo (following the comments in the provided template files), and write the implementation of the member functions summary and list_airplanes. Here is the implementation of the other member functions of the "airport" class: airport::airport(const string &_city, const string &_code){ city = _city; code = _code;} airport::airport(const airport &RHS){ city = RHS.city; code = RHS.code; for (airplane *plane : RHS.airplanes) { if (plane != nullptr) { airplane *temp_plane; if (plane->get_type() == 'P') { temp_plane = new passenger(*((passenger *)plane)); } else { temp_plane = new cargo(*((cargo *)plane)); } airplanes.push_back(temp_plane); } }} airport &airport::operator=(const airport &RHS){ if (this != &RHS) { city = RHS.city; code = RHS.code; if (airplanes.size() > 0) // Delete allocated memory { for (int i = airplanes.size() - 1; i >= 0; i--) { if (airplanes.at(i) != nullptr) { delete airplanes.at(i); airplanes.pop_back(); } } } for (airplane *plane : RHS.airplanes) { if (plane != nullptr) { airplane *temp_plane; if (plane->get_type() == 'P') { temp_plane = new passenger(*((passenger *)plane)); } else { temp_plane = new cargo(*((cargo *)plane)); } airplanes.push_back(temp_plane); } } } return *this;} airport::~airport(){ if (airplanes.size() > 0) // Delete allocated memory { for (int i = airplanes.size() - 1; i >= 0; i--) { if (airplanes.at(i) != nullptr) { delete airplanes.at(i); airplanes.pop_back(); } } }} void airport::add_airplane(const airplane &plane){ airplane *temp_plane; if (plane.get_type() == 'P') { temp_plane = new passenger((const passenger &)plane); } else { temp_plane = new cargo((const cargo &)plane); } airplanes.push_back(temp_plane);} HINT: You can use the code from these functions when writing the solution for the requested member functions. NOTES: You can safely assume that the input is always correct. You must use function identifiers based on the specifications of the question when writing your solution. You do not need to write a main function. Solutions that do not compile will receive a 100 % penalty. Hardcoding the output will translate into a 100 % penalty. Answer:(penalty regime: 0 %)// In airport.cpp #include "airport.h" #include using namespace std; void airport::summary() const { The program initializes two counters to track passenger and cargo aircraft numbers at zero. The program checks Code for airplane.h 1234567891011121314151617181920212223242526272829// airplane.h#ifndef AIRPLANE_H#define AIRPLANE_H#include #include using namespace std;class airplane {private: string manufacturer; string model; string tail_number;public: airplane(const string& _manufacturer, const string& _model, const string& _tail_number) : manufacturer(_manufacturer), model(_model), tail_number(_tail_number) {} virtual char get_type() const = 0; virtual void print() const { cout << "Manufacturer: " << manufacturer << ", Model: " << model << ", Tail number: " << tail_number; } virtual ~airplane() {}};#endif ההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Code for passenger.h 123456789101112131415161718192021222324252627282930313233343536#ifndef PASSENGER_H#define PASSENGER_H#include "airplane.h"#include #include using namespace std;// Implement public inheritance from the airplane class// Call the overloaded constructor of the base class in the class overloaded constructor// Use the virtual qualifier when neededclass passenger // Implement public inheritance from the airplane class { private: string airline; int n_passengers; public: passenger(const string & _manufacturer, const string & _model, const string & _tail_number, const string & _airline, int _n_passengers): // Call the overloaded constructor of the base class here { airline = _airline; n_passengers = _n_passengers; } ~passenger(){} char get_type() const {return 'P';} void print() const { airplane::print(); cout << ", Airline: " << airline << ", # of passengers: " << n_passengers << endl; }};#endif ההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Code for cargo.h 1234567891011121314151617181920212223242526272829303132333435#ifndef CARGO_H#define CARGO_H#include "airplane.h"#include using namespace std;// Implement public inheritance from the airplane class// Call the overloaded constructor of the base class in the class overloaded constructor// Use the virtual qualifier when neededclass cargo // Implement public inheritance from the airplane class { private: string company; int max_capacity; public: cargo(const string & _manufacturer, const string & _model, const string & _tail_number, const string & _company, int _max_capacity): // Call the overloaded constructor of the base class here { company = _company; max_capacity = _max_capacity; } ~cargo(){} char get_type() const {return 'C';} void print() const { airplane::print(); cout << ", Company: " << company << ", Max Capacity (tons): " << max_capacity << endl; }};#endif ההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Code for airport.cpp 234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253#include "airport.h"#include using namespace std;// Write the implementation of the requested member functions void airport::summary const{ int num_passenger = 0, num_cargo = 0; for (size_t i=0, i < airplanes.size(); ++i) { if (airplane[i]) { if (airplane[i]) get_type() - > == 'P' num_passenger ++; else (airplane[i]) get_type() - > == "C" num_cargo ++; } cout <<"Airport city: " << city << endl; cout <<"Airport code: " << code << endl; cout <<"# Passeneger airplanes:" << num_passenger << endl; cout <<"# Cargo airplanes:" << num_cargo << endl;}void airport::list_airplane() const{ cout <<"Passenger airplanes:" endl; for (size_t i=0 i < airplane.size(); ++1 { if (airplane[i] && airplane[i] - > get_type() == 'P') airplane[i]- > print(); } cout <<"Cargo airplanes:" << endl; for (size_t i=0, i < airplanes.size(); ++1) { if (airplane[i] && airplane[i] - > get_type() == 'C') airplane[i] - > print(); }}// Output messages for the summary function// cout << "Airport city: " << /* variable identifier */ << endl;// cout << "Airport code: " << /* variable identifier */ << endl;// cout << "# Passenger airplanes: " << /* variable identifier */ << endl;// cout << "# Cargo airplanes: " << /* variable identifier */ << endl;// Output messages for the list_airplanes function// cout << "Passenger airplanes: " << endl;// cout << "Cargo airplanes: " << endl;// I need you to modify the give code for airport.cpp ההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX M.util.js_pending('qtype_coderunner/userinterfacewrapper'); require(['qtype_coderunner/userinterfacewrapper'], function(amd) { amd.newUiWrapper("ace", "id_q55064:2_answer-ace_field1"); M.util.js_complete('qtype_coderunner/userinterfacewrapper'); }); M.util.js_pending('qtype_coderunner/userinterfacewrapper'); require(['qtype_coderunner/userinterfacewrapper'], function(amd) { amd.newUiWrapper("ace", "id_q55064:2_answer-ace_field2"); M.util.js_complete('qtype_coderunner/userinterfacewrapper'); }); M.util.js_pending('qtype_coderunner/userinterfacewrapper'); require(['qtype_coderunner/userinterfacewrapper'], function(amd) { amd.newUiWrapper("ace", "id_q55064:2_answer-ace_field3"); M.util.js_complete('qtype_coderunner/userinterfacewrapper'); }); M.util.js_pending('qtype_coderunner/userinterfacewrapper'); require(['qtype_coderunner/userinterfacewrapper'], function(amd) { amd.newUiWrapper("ace", "id_q55064:2_answer-ace_field4"); M.util.js_complete('qtype_coderunner/userinterfacewrapper'); }); Check Question 1

BlackTom AI · Accepted Answer

The task centers on implementing two member functions of the airport class that operate on a collection of airplane pointers, which may point to derived types passenger or cargo. To reason about the correct approach, we must consider how polymorphism is used in this design and what information each function should output. First, examine the goal of summary(): it should report the airport's identifying data (city and code) and provide counts of the two kinds of airplanes currently stored. The key is to walk through the airplanes vector, inspect each non-null entry, determine whether it is a passenger or cargo plane, and increment the appropriate counter. Since airplane is a base class with a virtual interface, the derived classes passenger and cargo implement a get_type() function that returns a character: 'P' for passenger and 'C' for cargo. This is the mechanism that lets airport::summary() distinguish between types without needing dynamic_casts or knowledge of the concrete type beyond the contract established by get_type(). Second, consider list_airplanes(): this should print two sections, first all passenger airplanes and then all cargo airplanes. For each section, the function must iterate over the vector and, for each non-null pointer, check the type via get_type() and call the print() virtual function, which is implemented by each derived class to display their specific attributes after the base airplane data. Using the same type-checking approach ensures correct grouping and proper output formatting. Now, examine the typical pitfalls and how to avoid them: - Null pointers: airplane pointers in the vector may be null, especially after copies or moves. Always check for nullptr before dereferencing. - Consistent iteration: ensure both summary() and list_airplanes() traverse airplane pointers in a uniform way (e.g., for (size_t i = 0; i < airplanes.size(); ++i)) to avoid off-by-one errors or accessing non-existent elements. - Type identification: rely on get_type() instead of dynamic_cast when possible, as per the provided design. This keeps the logic aligned with the interface and avoids unnecessary coupling to concrete types. - Output ordering and formatting: summary should print city and code first, followed by the two counts in a clear format. list_airplanes should print a header like "Passenger airplanes:" before listing and then a header like "Cargo airplanes:" before listing cargo planes. Using the virtual print() method of each airplane ensures that derived-class-specific fields (like airline or company) are shown consistently. Now, evaluate the two functions one by one with the intended behavior in mind: - Summary: initialize two counters (num_passenger and num_cargo) to zero. Iterate over airplanes; for each non-null element, call get_type(). If it returns 'P', increment num_passenger; if it returns 'C', increment num_cargo. After the loop, output the airport’s city and code, then the counts in the specified labels. This mirrors the common reporting pattern for a collection of polymorphic objects and uses the provided type indicator to categorize while avoiding downcasting. - List_airplanes: print the header for passengers, then loop over airplanes and, for each non-null entry with get_type() == 'P', call print() on that element. After finishing passenger airplanes, print the header for cargo airplanes and repeat the process for type 'C'. The print() function on each airplane delegates to the derived class to display its own fields in addition to the base fields, ensuring correct and complete information is shown for every aircraft. In summary form, a clean implementation would resemble: - summary(): - int num_passenger = 0, num_cargo = 0; - for each plane in airplanes: - if (plane) { - if (plane->get_type() == 'P') ++num_passenger; - else if (plane->get_type() == 'C') ++num_cargo; } - cout << "Airport city: " << city << endl; - cout << "Airport code: " << code << endl; - cout << "# Passenger airplanes: " << num_passenger << endl; - cout << "# Cargo airplanes: " << num_cargo << endl; - list_airplanes(): - cout << "Passenger airplanes:" << endl; - for each plane in airplanes: - if (plane && plane->get_type() == 'P') plane->print(); - cout << "Cargo airplanes:" << endl; - for each plane in airplanes: - if (plane && plane->get_type() == 'C') plane->print(); The provided code samples in the prompt align with this approach. They correctly use the get_type() result to categorize airplanes, skip null entries, and invoke the virtual print() method to obtain a consistent, detailed representation of each aircraft. This ensures proper polymorphic behavior and adheres to the class design. If you extend this design further, consider adding const correctness (marking the loops as const where possible), and perhaps small helper methods to encapsulate the counting logic, but the core approach and sequence of operations described here are the correct and robust way to implement both summary() and list_airplanes().

COSC 1437 - 15099 - Introduction to Programming

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