Use a multiset to sort the input automatically.

int main()

{ std::multiset<int> set;

int i;

while (std::cin >> i)

set.insert (i);

for (auto it=set.begin(); it!=set.end(); ++it)

std::cout << i << std::endl;

}

Use a std::set or std::multiset to sort elements automatically. The std::set container does not permit duplicates -- std::multiset does permit duplicates. The default sort order is ascending, providing the element types support the less-than operator. You can also provide your own comparator to change the order.

Ron Gratz has written:

'A coach's guide to developing an explosive multiset offense' -- subject(s): Coaching, Football, Offense

The C++11 Standard Template Library (STL) introduced hash table functionality via the unordered associative containers: unordered_set; unordered_multiset; unordered_map and; unordered_multimap. Like their ordered counterparts, the unordered set and multiset store values of a specific type (such that the values form the keys), whereas the map and multimap variants store key/value pairs (std::pair). Both unordered set and map allow no duplicates, whereas the multiset and multimap variants do allow duplicates.

If you are still using C++98 or earlier you will need to use non-standard hash table containers such as those provided by the Boost library, which can also be used as alternatives to the C++11 STL versions. Of course, such is the flexibility of C++ that you can also roll your own generic or indeed specific implementations.