void rehash( size_type count );
Sets the number of buckets to
count and rehashes the container, i.e. puts the elements into appropriate buckets considering that total number of buckets has changed. If the new number of buckets makes load factor more than maximum load factor (count < size() / max_load_factor()), then the new number of buckets is at least size() / max_load_factor().
|count||-||new number of buckets|
 Return value
average case linear in the size of the container, worst case quadratic.
rehash(0) may be used to force an unconditional rehash, such as after suspension of automatic rehashing by temporary increasing
 See also
| reserves space for at least the specified number of elements.|
This regenerates the hash table.
(public member function)