Calling a function pointer causes an error [closed] - c++

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I am trying to build a dynamic array of objects using pointers arithmetic. However, the compiler return the following error in this line in the main.cpp
(*(lista+n))(id1,seleccion1,edad1,camiseta1);
error: no match for call to '(jugador) (int &, int & short, short int &, short int &)'
any suggestion is welcome, thanks.
This is the class.
class jugador
{
private:
int id;
short seleccion;
short edad;
short camiseta;
public:
jugador();
jugador(int ID, short SELECCION, short EDAD, short CAMISETA);
int obtener_id();
short obtener_seleccion();
short obtener_edad();
short obtener_camiseta();
void cambiar_id(int nueva_id);
void cambiar_seleccion(short nueva_seleccion);
void cambiar_edad(short nueva_edad);
void cambiar_camiseta(short nueva_edad);
void cambiar_todo(int nueva_ID, short nueva_SELECCION, short nueva_EDAD, short nueva_CAMISETA);
void mostrar_jugador();
};
The constructors...
jugador::jugador()
{
id=999999;
seleccion=32;
edad=99;
camiseta=99;
}
jugador::jugador(int ID, short SELECCION, short EDAD, short CAMISETA)
{
id=ID;
seleccion=SELECCION;
edad=EDAD;
camiseta=CAMISETA;
}
Here is the full code.

Answer 1

Is there a special reason you are not using std::vector<jugador> Check this thread for the advantages of replacing realloc with vector
You have not given enough information so here is what I can tell from the looks of the error:
(*(lista+n))(id1,seleccion1,edad1,camiseta1);
that is NOT a function pointer, it's not even pointing to a function in the first place.
It seems like you are trying to construct an array of jugador by moving the lista pointer. If that is what you want to do then you can do late initialization.
jugador * lista; //< unitialized pointer
int n = 11; //< your number of players, lets suppose 11
lista = new jugador[11]; // now you have an array of jugadores
for(int i = 0; i != n; ++i)
{
lista[i] = jugador(id1,seleccion1,edad1,camiseta1);
}
// use your jugadores, let's suppose you want to use the tenth jugador
jugador *iterator = lista;
iterator+10;
use(*iterator); //*iterator variable holds your 10th jugador object
delete[] lista;
You are using realloc in your code, I suggest you try new and delete instead. Or else provide an explanation of why using realloc is a good choice.
Another thing I noticed in your code is that you don't free the memory you are using. Thus you have a memory leak.
If you need more jugador the use std::copy to achieve that
// let's say in this point you need 20 jugador more
jugador * newlista = new jugador[n+20];
std::copy(lista, lista+11, newlista);
delete[] lista; //you delete the old buffer
for(int i = 11; i != n+20; ++i)
{
newlista[i] = jugador(id1,seleccion1,edad1,camiseta1);
}
// and now newlista has your jugadores, you can even make a function that does that
delete[] newlista ; // delete your jugadores

Answer 2

I am completely agreed with Claudiordgz's response. However, if you want to call the constructor with parameters (without making extra copies) you will need to make an array of pointers instead of an array of objects. I am pasting a version of your code with that. However, I still think that a version using vectors is safer and superior.
Code:
int main()
{
int id1;
short seleccion1, edad1, camiseta1;
jugador arreglo[5];
int n = 0, i;
char opcion = 's';
jugador **lista=NULL;
while (opcion == 's')
{
lista = new jugador*[n];
cout<<"id: "<<endl;
cin>>id1;
cout<<"Seleccion: "<<endl;
cin>>seleccion1;
cout<<"Edad: "<<endl;
cin>>edad1;
cout<<"Camiseta: "<<endl;
cin>>camiseta1;
lista[n] = new jugador(id1,seleccion1,edad1,camiseta1);
n++;
cout << "Desea ingresar otro elemento? (s/n): ";
cin >> opcion;
}
cout << "\nArreglo completo\n";
for (i=0; i<n; i++)
{
lista[n].mostrar_jugador();
}
//deallocating memory
for (int i=0; i<n; i++)
{
delete jugador[i];
}
delete [] jugador;
return 0;
}