2009/10/15 Arun Raghavan :

Do the underlying hashtable implementations of unordered_map/multimap store a size field (i.e. do they support a constant-time size function)? Same query about the load factor and bucket sizes.

Size is stored in a member variable, so it's just a member lookup. Load factor is calculated by dividing the size by the number of buckets, so it's constant time but a bit slower. Bucket size is o(n) where n is the size of the bucket. Daniel