c++ override function of base class - c++

Question

I'm pretty new to object oriented programming in C++, and I can't find a solution to the following problem, I hope this is even possible.
I've got 3 classes: Base and Child, Child2.
All of them got the function talk();.
I want to store Base, Child and Child2 objects in an array, and iterate through them and execute their talk() functions.
This is what I want them to print:
- Base: "base"
- Child: "child"
- Child2: "child2"
Here are my classes:
class Base {
public:
virtual void talk() {
printf("base\n");
}
}
class Child : public Base {
public:
using Base:draw;
void talk() {
printf("child\n");
}
}
class Child2 : public Base {
public:
using Base:draw;
void talk() {
printf("child2\n");
}
}
here is my array:
Base objects[3];
objects[0] = Base();
objects[1] = Child();
objects[2] = Child2();
for(int i = 0; i < 3; i++) {
objects[i]->talk();
}
And the output should be:
base
child
child2

Answer 1

Your code is slicing the objects. When you assign a variable of the base class to the value of derived class, you end up with a base object. At this point, nothing is left of the original derived class, all you have is a base class.
In C++ the way to treat objects polymorphically - that is, to retain the information of original type - is to use either a reference or a pointer. However, you can not put references into arrays.
Which means, you need an array of pointers - but not raw pointers. You want so-called smart pointers. Putting it all together, this is how your code should look like:
std::unique_ptr<Base> objects[3] = {new Base(), new Child(), new Child2()};
for(int i = 0; i < 3; i++) {
objects[i]->talk();
}

Answer 2

Perhaps something like this?
#include <iostream>
#include <cstdio>
class Base
{
public:
virtual void talk()
{
printf("base\n");
}
};
class Child : public Base
{
public:
void talk()
{
printf("child\n");
}
};
class Child2 : public Base
{
public:
void talk()
{
printf("child2\n");
}
};
int main()
{
Base** objects;
objects = new Base * [3];
objects[0] = new Base();
objects[1] = new Child();
objects[2] = new Child2();
for(int i = 0; i < 3; i++)
objects[i]->talk();
}
Output is:
base
child
child2

Answer 3

So something like:
#include <stdio.h>
class Base {
public:
virtual void talk() {
printf("base\n");
}
};
class Child : public Base {
public:
void talk()
{
printf("child\n");
}
};
class Child2 : public Base {
public:
void talk()
{
printf("child2\n");
}
};
int main()
{
Base* objects[3];
objects[0] = new Base();
objects[1] = new Child();
objects[2] = new Child2();
for(int i = 0; i < 3; i++) {
objects[i]->talk();
}
}