Question

I have a little question about a code example in C++.

vector<Cat> v;
Cat c;
v.push_back(c);
Cat d = v[0];

In this piece of code, how many objects are created?

Answer 1

At least three:

vector<Cat> v;
Cat c;  // default construction
v.push_back(c); // copy construction of v[0] from c
Cat d = v[0];  // copy construction of d from v[0]

Edit: Note that I only count Cat objects here, because it doesn’t make sense to ask how many objects in total are created, because that would be implementation specific (how is std::vector implemented? What does Cat do? …)