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Dynamically Allocated an Array of Classes

briscoeeee (6)
I am trying to write a test file that dynamically allocates an array that i use to call the parent and two child classes. They will then call their own print functions.I d o not know if I am even doing it right but I keep getting the errors with the main every time. Even if i change something. They area all separate files in a project as well.

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class Ship
{
	protected:
		string shipName;
		string year;
	public:
		Ship();
		Ship(string, string);
		virtual void print();
};

Ship::Ship()
{
	shipName =  " ";
	year = " ";
}

Ship::Ship(string myName, string myYear) 	// Constructor
{
	//strcpy(shipName, myName);
	//strcpy(year, myYear);
	shipName = myName;
	year = myYear;
}

void Ship::print()
{
	cout << shipName << endl;
	cout << year << endl;
}

class CargoShip : public Ship
{
	protected:
		int load;		
	public:
		CargoShip();
		CargoShip(string, string, int);
		virtual void print();

};

CargoShip::CargoShip() : Ship()
{
	load = 0;
}

CargoShip::CargoShip(string myName, string myYear, int myLoad) :
	Ship(myName, myYear)
{
	load = myLoad;
}

void CargoShip::print()
{
	cout << shipName << endl;
	cout << load << endl;
}

class CruiseShip : public Ship
{
	protected:
		int passNum;
	
	public:
		CruiseShip();
		CruiseShip(string, string, int);
		virtual void print();

};

CruiseShip::CruiseShip() : Ship()
{
		passNum = 0;
}

CruiseShip::CruiseShip(string myName, string myYear, int myNum) :
	Ship(myName, myYear)
{
	passNum = myNum;
}

void CruiseShip::print()
{
	cout << shipName << endl;
	cout << passNum << endl;
}



#include "Ship.h"
#include "Cruise.h"
#include "Cargo.h"
#include <iostream>
#include <string>
using namespace std;

int main()
{

	shipArray[3]
	{
		shipArray[0] = new Ship("S.S. Shippy", "1997");
		shipArray[1] = new Cruise("S.S. La Cruise", "2017", 20);
		shipArray[2] = new Cargo("S.S El Cargo", "1845", 300);
	};
	
	shipArray[0].print();
	shipArray[1].print();
	shipArray[2].print();

	delete [] shipArray;
	
	/*CruiseShip cruise("S.S. La Cruise", "2017", 20);
	CargoShip cargo("S.S El Cargo", "1845", 300);
	
	ship.print();
	cruise.print();
	cargo.print();*/

/*	Ship ship("S.S. Shippy", "2017");
	ship.print();
		
	CruiseShip cruise("S.S. La Cruise", "2017", 20);
	cruise.print();
	
	CargoShip cargo("S.S El Cargo", "1845", 300);
	cargo.print();
*/	
	
	return 0;
}
Last edited on
Repeater (3046)
Looks like you're trying to make an array of 3 Ship*. Three pointers.

The array you're creating here isn't dynamic. The objects being pointed to by each of the Ship* are.

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#include <string>
#include <iostream>

using namespace std;

class Ship
{
	protected:
		string shipName;
		string year;
	public:
		Ship();
		Ship(string, string);
		virtual void print();
};

Ship::Ship()
{
	shipName =  " ";
	year = " ";
}

Ship::Ship(string myName, string myYear) 	// Constructor
{
	//strcpy(shipName, myName);
	//strcpy(year, myYear);
	shipName = myName;
	year = myYear;
}

void Ship::print()
{
	cout << shipName << endl;
	cout << year << endl;
}

class CargoShip : public Ship
{
	protected:
		int load;		
	public:
		CargoShip();
		CargoShip(string, string, int);
		virtual void print();

};

CargoShip::CargoShip() : Ship()
{
	load = 0;
}

CargoShip::CargoShip(string myName, string myYear, int myLoad) :
	Ship(myName, myYear)
{
	load = myLoad;
}

void CargoShip::print()
{
	cout << shipName << endl;
	cout << load << endl;
}

class CruiseShip : public Ship
{
	protected:
		int passNum;
	
	public:
		CruiseShip();
		CruiseShip(string, string, int);
		virtual void print();

};

CruiseShip::CruiseShip() : Ship()
{
		passNum = 0;
}

CruiseShip::CruiseShip(string myName, string myYear, int myNum) :
	Ship(myName, myYear)
{
	passNum = myNum;
}

void CruiseShip::print()
{
	cout << shipName << endl;
	cout << passNum << endl;
}

int main()
{

Ship* shipArray[3];

shipArray[0] = new Ship("S.S. Shippy", "1997");
shipArray[1] = new CruiseShip("S.S. La Cruise", "2017", 20);
shipArray[2] = new CargoShip("S.S El Cargo", "1845", 300);

shipArray[0]->print();
shipArray[1]->print();
shipArray[2]->print();

delete shipArray[0];
delete shipArray[1];
delete shipArray[2];

return 0;
}


https://ideone.com/0hwmB9
Last edited on
briscoeeee (6)
Thank you so much! I had something like that before but I couldn't get it to work the way i wanted it to. I got it to work with your solution. Thank you again!
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