Compilare: user.cpp: In member function ‘bool UndirectedGraph<NNodes>::LeeStruct::operator<(const UndirectedGraph<NNodes>::LeeStruct&) const’: user.cpp:94:9: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In instantiation of ‘bool UndirectedGraph<NNodes>::LeeStruct::operator<(const UndirectedGraph<NNodes>::LeeStruct&) const [with int NNodes = 805]’: /usr/include/c++/6/bits/stl_function.h:386:20: required from ‘constexpr bool std::less<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = UndirectedGraph<805>::LeeStruct]’ /usr/include/c++/6/bits/predefined_ops.h:125:18: required from ‘constexpr bool __gnu_cxx::__ops::_Iter_comp_iter<_Compare>::operator()(_Iterator1, _Iterator2) [with _Iterator1 = __gnu_cxx::__normal_iterator<UndirectedGraph<805>::LeeStruct*, std::vector<UndirectedGraph<805>::LeeStruct, std::allocator<UndirectedGraph<805>::LeeStruct> > >; _Iterator2 = __gnu_cxx::__normal_iterator<UndirectedGraph<805>::LeeStruct*, std::vector<UndirectedGraph<805>::LeeStruct, std::allocator<UndirectedGraph<805>::LeeStruct> > >; _Compare = std::less<UndirectedGraph<805>::LeeStruct>]’ /usr/include/c++/6/bits/stl_heap.h:217:14: required from ‘void std::__adjust_heap(_RandomAccessIterator, _Distance, _Distance, _Tp, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<UndirectedGraph<805>::LeeStruct*, std::vector<UndirectedGraph<805>::LeeStruct, std::allocator<UndirectedGraph<805>::LeeStruct> > >; _Distance = int; _Tp = UndirectedGraph<805>::LeeStruct; _Compare = __gnu_cxx::__ops::_Iter_comp_iter<std::less<UndirectedGraph<805>::LeeStruct> >]’ /usr/include/c++/6/bits/stl_heap.h:335:22: required from ‘void std::__make_heap(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<UndirectedGraph<805>::LeeStruct*, std::vector<UndirectedGraph<805>::LeeStruct, std::allocator<UndirectedGraph<805>::LeeStruct> > >; _Compare = __gnu_cxx::__ops::_Iter_comp_iter<std::less<UndirectedGraph<805>::LeeStruct> >]’ /usr/include/c++/6/bits/stl_heap.h:388:23: required from ‘void std::make_heap(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator<UndirectedGraph<805>::LeeStruct*, std::vector<UndirectedGraph<805>::LeeStruct, std::allocator<UndirectedGraph<805>::LeeStruct> > >; _Compare = std::less<UndirectedGraph<805>::LeeStruct>]’ /usr/include/c++/6/bits/stl_queue.h:447:23: required from ‘std::priority_queue<_Tp, _Sequence, _Compare>::priority_queue(const _Compare&, _Sequence&&) [with _Tp = UndirectedGraph<805>::LeeStruct; _Sequence = std::vector<UndirectedGraph<805>::LeeStruct, std::allocator<UndirectedGraph<805>::LeeStruct> >; _Compare = std::less<UndirectedGraph<805>::LeeStruct>]’ user.cpp:50:41: required from ‘int UndirectedGraph<NNodes>::Type2() [with int NNodes = 805]’ user.cpp:115:32: required from here user.cpp:93:18: warning: statement has no effect [-Wunused-value] Dist < Other.Dist; ~~~~~^~~~~~~~~~~~