Question

I think the question title is clear enough: is is possible to stable_sort() a std::list in C++? Or do I have to convert it to a std::vector?

I’m asking because I tried a simple example and it seems to require RandomAccessIterators, which a linked list doesn’t have. So, how do I stable sort a std::list()?

EDIT: sample code that gives me an error:

#include <list>
#include <algorithm>
// ...
list<int> the_list;
stable_sort(the_list.begin(), the_list.end());

g++ gives me around 30 lines of errors (too long to paste), with some of them referring to RandomAccessIterators (and something called _merge_sort_loop). It’s a little weird, since I’ve seen some merge sort implementations for linked lists and they are pretty much ‘sequential’.

Answer 1

std::list::sort is already stable. From the standard, section 23.2.24: “Notes: Stable: the relative order of the equivalent elements is preserved.”