Can a pointer to base point to an array of derived objects?

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You cannot index like that. You have allocated an array of Rectangles and stored a pointer to the first in shapes. When you do shapes[1] you’re dereferencing (shapes + 1). This will not give you a pointer to the next Rectangle, but a pointer to what would be the next Shape in a presumed array of Shape. Of course, this is undefined behaviour. In your case, you’re being lucky and getting a crash.

Using a pointer to Rectangle makes the indexing work correctly.

int main()
{
   Rectangle * shapes = new Rectangle[10];
   for (int i = 0; i < 10; ++i) shapes[i].draw();
}

If you want to have different kinds of Shapes in the array and use them polymorphically you need an array of pointers to Shape.

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