map vs. hash_map in C++ -


I have a question in hash_map and map c ++ I understand that the map is in STL, but hash_map is not standard, what is the difference between the two?

These are implemented in a very different way.

hash_map (use unordered_map in TR1 and Boost; instead, use them) Use a hash table where the key is in a slot in the table The value is pushed and the value is stored in the list

Map is applied as a balanced binary search tree (usually a red / black tree).

An unordered_map should give slightly better performance to access the known elements of the archive, but there will be additional useful features in a map (as it is sorted Is stored in order, which allows traversal ending from the beginning) will be faster on insert and delete from unordered_map a map .


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