(->) arrow operator and (.) dot operator , class pointer

Question

In C++ we know that for a pointer of class we use (->) arrow operator to access the members of that class like here:

#include 
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Answer 1

Perhaps its insightful to consider that, given

myclass obj;
auto p = &obj;  // avoid `new` with plain pointers. That combination is
               //  safer replaced by unique_ptr or std::vector.

the following will all work and are equivalent:

p->setdata(5, 6);
(*p).setdata(5, 6);
p[0].setdata(5, 6);
0[p].setdata(5, 6);

Showing that [] is really a pointer-dereferencing operator, just with the extra functionality that you can add offsets into a plain C-array.

It's generally questionable to use C-arrays in C++ code; the obvious alternative to your example is std::vector:

std::vector array(10);

Here, array[n] can be used much like previously p[n], but

• You don't get any stupid pointer-ideas, because there are no pointers in the interface
• You get proper automatic memory management, i.e. when the array goes out of scope it automatically deletes the objects and its memory
• You can get bounds-checks if you want (array.at(n))
• You can easily loop over the whole array, with (C++11) for(auto& obj: array){...}.