Are c++ std::map<string,string> ordered?
c++
Solution
are STL maps ordered?
Yes, a `std::map<K,V>` is ordered based on the key, `K`, using `std::less<K>` to compare objects, by default.
So if I iterate over it, it will iterate with the first insert string first?
No. It will iterate based on the sorted order, not the order that you inserted elements. In the case of `std::string`, it sorts in lexicographic order (alphabetic order).
If you want to iterate based on the insertion order, you're better off using a sequence container, such as a `std::vector` or a `std::list`.
Problem
are STL maps ordered? Specifically I need to know if std::map is ordered. So if I iterate over it, it will iterate with the first insert string first. So will the below iterate A, C then B consistantly? ``` std::map<string,string> str_map; str_map.insert(std::make_pair("A","Data")); str_map.insert(std::make_pair("C","Data")); str_map.insert(std::make_pair("B","Data")); ```