C++ Array of pointers to an abstract class
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I have this homework for my OOP class which I hope someone can check for me:
Make an abstract class ElementOnMap which contains a unique id (int), a type (char array) and a static var #ofElements. Than create a class Map with dimensions of the map and a matrix of pointers to objects of class Element. It should have the following functions:
...
-a copy constructor!
...
Than make a sub class Island and a sub class Ship which inherit the class Element, which redefine the abstract method from Element, ...
So this is Element.h
class Element
{
protected:
static int numEl;
int id;
char type[16];
public:
char * type()
{
char *p = type;
return p;
}
virtual void print() = 0;
};
class Island :public Element
{
char name[16];
int numPeople;
public:
Island();
Island(char*, int);
void print();
};
This is my Element.cpp:
#include"Element.h"
#include<string>
#include<iostream>
using namespace std;
int Element::numEl = 0;
Island::Island()
{
id = numEl;
numEl++;
}
Island::Island(char* naz, int a) :numPeople(a)
{
strcpy_s(name, naz);
type[0] = 'I';
type[1] = 's';
type[2] = 'l';
type[3] = 'a';
type[4] = 'n';
type[5] = 'd';
type[6] = '';
id = numEl;
numEl++;
}
void Island::print()
{
cout << "ID elementa: " << id << "Tip elementa: " << type;
cout << "Ime ostrva: " << name << "Broj stanovnika: " << numPeople << endl;
}
and finally, Map.h:
class Mapa
{
int m, n;
Element ***Matrix;
public:
Mapa(int, int);
Mapa(const Mapa &M);
~Mapa();
};
Mapa::Mapa(int a, int b):m(a), n(b)
{
Matrix = new Element**[m];
for (int i = 0; i < m; i++)
Matrix[i] = new Element*[n];
}
Mapa::Mapa(const Mapa & M)
{
this->m = M.m;
this->n = M.n;
Matrix = new Element**[m];
for (int i = 0; i < m; i++)
Matrix[i] = new Element*[n];
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
{
*Matrix[i][j] = *(M.Matrix[i][j]);
}
}
Mapa::~Mapa()
{
delete Matrix;
}
Am I declaring the pointer matrix correctly and is my copy constructor any good? I get that i need a deep copy cause i'm working with pointers, but this pointer inception is really making me feel dumb. Also, do i need a constructor for the abstract Element class, since it cant be instantiated?
c++ array pointers
asked 11 hours ago
dukki98dukki98
61
New contributor
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
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add a comment |
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I have this homework for my OOP class which I hope someone can check for me:
Make an abstract class ElementOnMap which contains a unique id (int), a type (char array) and a static var #ofElements. Than create a class Map with dimensions of the map and a matrix of pointers to objects of class Element. It should have the following functions:
...
-a copy constructor!
...
Than make a sub class Island and a sub class Ship which inherit the class Element, which redefine the abstract method from Element, ...
So this is Element.h
class Element
{
protected:
static int numEl;
int id;
char type[16];
public:
char * type()
{
char *p = type;
return p;
}
virtual void print() = 0;
};
class Island :public Element
{
char name[16];
int numPeople;
public:
Island();
Island(char*, int);
void print();
};
This is my Element.cpp:
#include"Element.h"
#include<string>
#include<iostream>
using namespace std;
int Element::numEl = 0;
Island::Island()
{
id = numEl;
numEl++;
}
Island::Island(char* naz, int a) :numPeople(a)
{
strcpy_s(name, naz);
type[0] = 'I';
type[1] = 's';
type[2] = 'l';
type[3] = 'a';
type[4] = 'n';
type[5] = 'd';
type[6] = '';
id = numEl;
numEl++;
}
void Island::print()
{
cout << "ID elementa: " << id << "Tip elementa: " << type;
cout << "Ime ostrva: " << name << "Broj stanovnika: " << numPeople << endl;
}
and finally, Map.h:
class Mapa
{
int m, n;
Element ***Matrix;
public:
Mapa(int, int);
Mapa(const Mapa &M);
~Mapa();
};
Mapa::Mapa(int a, int b):m(a), n(b)
{
Matrix = new Element**[m];
for (int i = 0; i < m; i++)
Matrix[i] = new Element*[n];
}
Mapa::Mapa(const Mapa & M)
{
this->m = M.m;
this->n = M.n;
Matrix = new Element**[m];
for (int i = 0; i < m; i++)
Matrix[i] = new Element*[n];
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
{
*Matrix[i][j] = *(M.Matrix[i][j]);
}
}
Mapa::~Mapa()
{
delete Matrix;
}
Am I declaring the pointer matrix correctly and is my copy constructor any good? I get that i need a deep copy cause i'm working with pointers, but this pointer inception is really making me feel dumb. Also, do i need a constructor for the abstract Element class, since it cant be instantiated?
c++ array pointers
asked 11 hours ago
dukki98dukki98
61
New contributor
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
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Does your program work? It does not work, the question is off-topic at this site.
$endgroup$
– R Sahu
8 hours ago
add a comment |
$begingroup$
I have this homework for my OOP class which I hope someone can check for me:
Make an abstract class ElementOnMap which contains a unique id (int), a type (char array) and a static var #ofElements. Than create a class Map with dimensions of the map and a matrix of pointers to objects of class Element. It should have the following functions:
...
-a copy constructor!
...
Than make a sub class Island and a sub class Ship which inherit the class Element, which redefine the abstract method from Element, ...
So this is Element.h
class Element
{
protected:
static int numEl;
int id;
char type[16];
public:
char * type()
{
char *p = type;
return p;
}
virtual void print() = 0;
};
class Island :public Element
{
char name[16];
int numPeople;
public:
Island();
Island(char*, int);
void print();
};
This is my Element.cpp:
#include"Element.h"
#include<string>
#include<iostream>
using namespace std;
int Element::numEl = 0;
Island::Island()
{
id = numEl;
numEl++;
}
Island::Island(char* naz, int a) :numPeople(a)
{
strcpy_s(name, naz);
type[0] = 'I';
type[1] = 's';
type[2] = 'l';
type[3] = 'a';
type[4] = 'n';
type[5] = 'd';
type[6] = '';
id = numEl;
numEl++;
}
void Island::print()
{
cout << "ID elementa: " << id << "Tip elementa: " << type;
cout << "Ime ostrva: " << name << "Broj stanovnika: " << numPeople << endl;
}
and finally, Map.h:
class Mapa
{
int m, n;
Element ***Matrix;
public:
Mapa(int, int);
Mapa(const Mapa &M);
~Mapa();
};
Mapa::Mapa(int a, int b):m(a), n(b)
{
Matrix = new Element**[m];
for (int i = 0; i < m; i++)
Matrix[i] = new Element*[n];
}
Mapa::Mapa(const Mapa & M)
{
this->m = M.m;
this->n = M.n;
Matrix = new Element**[m];
for (int i = 0; i < m; i++)
Matrix[i] = new Element*[n];
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
{
*Matrix[i][j] = *(M.Matrix[i][j]);
}
}
Mapa::~Mapa()
{
delete Matrix;
}
Am I declaring the pointer matrix correctly and is my copy constructor any good? I get that i need a deep copy cause i'm working with pointers, but this pointer inception is really making me feel dumb. Also, do i need a constructor for the abstract Element class, since it cant be instantiated?
c++ array pointers
asked 11 hours ago
dukki98dukki98
61
New contributor
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
I have this homework for my OOP class which I hope someone can check for me:
Make an abstract class ElementOnMap which contains a unique id (int), a type (char array) and a static var #ofElements. Than create a class Map with dimensions of the map and a matrix of pointers to objects of class Element. It should have the following functions:
...
-a copy constructor!
...
Than make a sub class Island and a sub class Ship which inherit the class Element, which redefine the abstract method from Element, ...
So this is Element.h
class Element
{
protected:
static int numEl;
int id;
char type[16];
public:
char * type()
{
char *p = type;
return p;
}
virtual void print() = 0;
};
class Island :public Element
{
char name[16];
int numPeople;
public:
Island();
Island(char*, int);
void print();
};
This is my Element.cpp:
#include"Element.h"
#include<string>
#include<iostream>
using namespace std;
int Element::numEl = 0;
Island::Island()
{
id = numEl;
numEl++;
}
Island::Island(char* naz, int a) :numPeople(a)
{
strcpy_s(name, naz);
type[0] = 'I';
type[1] = 's';
type[2] = 'l';
type[3] = 'a';
type[4] = 'n';
type[5] = 'd';
type[6] = '';
id = numEl;
numEl++;
}
void Island::print()
{
cout << "ID elementa: " << id << "Tip elementa: " << type;
cout << "Ime ostrva: " << name << "Broj stanovnika: " << numPeople << endl;
}
and finally, Map.h:
class Mapa
{
int m, n;
Element ***Matrix;
public:
Mapa(int, int);
Mapa(const Mapa &M);
~Mapa();
};
Mapa::Mapa(int a, int b):m(a), n(b)
{
Matrix = new Element**[m];
for (int i = 0; i < m; i++)
Matrix[i] = new Element*[n];
}
Mapa::Mapa(const Mapa & M)
{
this->m = M.m;
this->n = M.n;
Matrix = new Element**[m];
for (int i = 0; i < m; i++)
Matrix[i] = new Element*[n];
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
{
*Matrix[i][j] = *(M.Matrix[i][j]);
}
}
Mapa::~Mapa()
{
delete Matrix;
}
Am I declaring the pointer matrix correctly and is my copy constructor any good? I get that i need a deep copy cause i'm working with pointers, but this pointer inception is really making me feel dumb. Also, do i need a constructor for the abstract Element class, since it cant be instantiated?
c++ array pointers
c++ array pointers
asked 11 hours ago
dukki98dukki98
61
New contributor
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 11 hours ago
dukki98dukki98
61
New contributor
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 11 hours ago
dukki98dukki98
61
New contributor
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 11 hours ago
dukki98dukki98
61
asked 11 hours ago
dukki98dukki98
61
61
New contributor
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
dukki98 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$begingroup$
Does your program work? It does not work, the question is off-topic at this site.
$endgroup$
– R Sahu
8 hours ago
add a comment |
$begingroup$
Does your program work? It does not work, the question is off-topic at this site.
$endgroup$
– R Sahu
8 hours ago
$begingroup$
Does your program work? It does not work, the question is off-topic at this site.
$endgroup$
– R Sahu
8 hours ago
$begingroup$
Does your program work? It does not work, the question is off-topic at this site.
$endgroup$
– R Sahu
8 hours ago
add a comment |
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$begingroup$
Does your program work? It does not work, the question is off-topic at this site.
$endgroup$
– R Sahu
8 hours ago