Eroare de compilare: In file included from /usr/include/c++/6/bits/stl_algobase.h:64:0, from /usr/include/c++/6/bits/char_traits.h:39, from /usr/include/c++/6/ios:40, from /usr/include/c++/6/istream:38, from /usr/include/c++/6/fstream:38, from main.cpp:1: /usr/include/c++/6/bits/stl_pair.h: In instantiation of 'struct std::pair<const int, solutie>': /usr/include/c++/6/ext/aligned_buffer.h:85:34: required from 'struct __gnu_cxx::__aligned_buffer<std::pair<const int, solutie> >' /usr/include/c++/6/bits/hashtable_policy.h:246:43: required from 'struct std::__detail::_Hash_node_value_base<std::pair<const int, solutie> >' /usr/include/c++/6/bits/hashtable_policy.h:292:12: required from 'struct std::__detail::_Hash_node<std::pair<const int, solutie>, false>' /usr/include/c++/6/bits/hashtable_policy.h:1894:60: required from 'struct std::__detail::_Hashtable_alloc<std::allocator<std::__detail::_Hash_node<std::pair<const int, solutie>, false> > >' /usr/include/c++/6/bits/hashtable.h:170:11: required from 'class std::_Hashtable<int, std::pair<const int, solutie>, std::allocator<std::pair<const int, solutie> >, std::__detail::_Select1st, std::equal_to<int>, std::hash<int>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true> >' /usr/include/c++/6/bits/unordered_map.h:101:18: required from 'class std::unordered_map<int, solutie>' main.cpp:7:36: required from here /usr/include/c++/6/bits/stl_pair.h:200:11: error: 'std::pair<_T1, _T2>::second' has incomplete type _T2 second; /// @c second is a copy of the second object ^~~~~~ main.cpp:7:27: note: forward declaration of 'struct solutie' unordered_map<int, struct solutie> umap; ^~~~~~~ Non zero exit status: 1