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derived class constructor

gduong (26)
I need some help with my constructor in my gaspowered constructor.
GasPowered(double e, double f):Car(mak,mod) for some reason the mak,mod is red saying it is not declared. can some show me how to fix it? thank you

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


//class Car
class Car{
protected:
	string make;
	string model;
public:
	//constructor for car
	Car(string mak, string mod){
		make = mak;
		model = mod;}
string getMake(){return make;}
string getModel(){return model;}
	virtual void print_description(){cout <<"Car maker: " << getMake() << ", Model:" << getModel() << endl;}
};

class GasPowered: public Car{
private: 
	double engine_size;
	double fuel_tank_size;
public:
	GasPowered(double e, double f):Car(mak,mod){engine_size = e; fuel_tank_size = f;}
	virtual void print_description (){cout <<"Car maker: " << getMake() << ", Model:" << getModel() << endl;}
};
Last edited on
JLBorges (13770)
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class GasPowered: public Car{
private: 
	double engine_size;
	double fuel_tank_size;
public:
	//GasPowered(double e, double f):Car(mak,mod){engine_size = e; fuel_tank_size = f;}
        GasPowered( string mak, string mod, double e, double f ) : Car(mak,mod)
        {engine_size = e; fuel_tank_size = f;}

	 virtual void print_description () const // *** const
        {cout <<"Car maker: " << getMake() << ", Model:" << getModel() << endl;}
};


And make virtual void print_description() in the base class
virtual void print_description() const

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virtual void print_description() const { /* ... */ }
string getMake() const {return make;} // *** const
string getModel() const {return model;} // *** const
gduong (26)
Thank you. I fixed the problem but i ran into another one. It is not outputting anything to the screen when i try to call the class.

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


//class Car
class Car{
protected:
	string make;
	string model;
public:
	//constructor for car
	Car(string mak, string mod){
		make = mak;
		model = mod;}
string getMake()const{return make;}
string getModel()const{return model;}
	virtual void print_description() const{cout <<"Car maker: " << getMake() << ", Model:" << getModel() << endl;}
};
//classs Gaspowered
class GasPowered: public Car{
private: 
	double engine_size;
	double fuel_tank_size;
public:
 GasPowered( string mak, string mod, double e, double f ) : Car(mak,mod)
        {engine_size = e; fuel_tank_size = f;}
double getEngine_size() const{return engine_size;}
double getFuel_tank_size()const{return fuel_tank_size;}
	virtual void print_description ()const
{cout <<"Car maker: " << getMake() << ", Model:" << getModel() << "Engine size" << getEngine_size() << "Fuel tank size: " <<getFuel_tank_size() <<endl;}
};

int main()
{

	Car car1("Toyota", "Camry");
	GasPowered car2("Honda", "Accord",2.4, 15);
	return 0;
}
xismn (961)
You aren't calling print_description() anywhere.
gduong (26)
aww ok thanks. i tried calling it with a global function. any help to fix it will be appreciated. I am trying to pass by reference
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#include <iostream>
#include <string>
using namespace std;


//class Car
class Car{
protected:
	string make;
	string model;
public:
	//constructor for car
	Car(string mak, string mod){
		make = mak;
		model = mod;}
string getMake()const{return make;}
string getModel()const{return model;}
	virtual void print_description() const{cout <<"Car maker: " << getMake() << ", Model:" << getModel() << endl;}
};
//classs Gaspowered
class GasPowered: public Car{
private: 
	double engine_size;
	double fuel_tank_size;
public:
 GasPowered( string mak, string mod, double e, double f ) : Car(mak,mod)
        {engine_size = e; fuel_tank_size = f;}
double getEngine_size() const{return engine_size;}
double getFuel_tank_size()const{return fuel_tank_size;}
	virtual void print_description ()const
{cout <<"Car maker: " << getMake() << ", Model:" << getModel() << "Engine size" << getEngine_size() << "Fuel tank size: " <<getFuel_tank_size() <<endl;}
};

int main()
{

	Car car1("Toyota", "Camry");
	GasPowered car2("Honda", "Accord",2.4, 15);
	cout << get_specification(car1);
	cout << get_specification(car2);
	return 0;
}


string get_specification(string &car)
{
	 cout << car.print_description() << endl;
}
Last edited on
JLBorges (13770)
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// declaration
/*string*/ void /*get_specification*/print_specification( /*string &*/ const Car& car ) ;

int main()
{
	Car car1("Toyota", "Camry");
	GasPowered car2("Honda", "Accord",2.4, 15);

	// cout << get_specification(car1);
	// cout << get_specification(car2);
	// return 0;

        print_specification(car1) ;
        print_specification(car2) ;
}

// definition
/*string*/ void /*get_specification*/print_specification( /*string &*/ const Car& car )
{
	 /*cout << */ car.print_description() /*<< endl */ ;
}
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