Initial capacity of vector in C++

Question

What is the capacity() of an std::vector which is created using the default constuctor? I know that the size() is zero. Can we state t

Answer 1

As a slight addition to the other answers, I found that when running under debug conditions with Visual Studio a default constructed vector will still allocate on the heap even though the capacity starts at zero.

Specifically if _ITERATOR_DEBUG_LEVEL != 0 then vector will allocate some space to help with iterator checking.

https://docs.microsoft.com/en-gb/cpp/standard-library/iterator-debug-level

I just found this slightly annoying since I was using a custom allocator at the time and was not expecting the extra allocation.