What is the time complexity of std::sort() in the C++ standard library?

Question

What is the complexity of std::sort() in the C++ Standard Library? Which sort is applied? Is there any rule of applying any particular sorting algorithm there?<

Answer 1

If you mean std::sort():

This is from C++03 standard, section 25.3. The performance guarantee:

template
void sort(RandomAccessIterator first, RandomAccessIterator last);

template void sort(RandomAccessIterator first, RandomAccessIterator last,
    Compare comp);

1 Effects: Sorts the elements in the range [first, last).

2 Complexity: Approximately N log N (where N == last - first) comparisons on the average.