Eroare de compilare: user.cpp: In function 'void read()': user.cpp:27: error: no matching function for call to 'std::set<nod, std::less<nod>, std::allocator<nod> >::find(int&)' /usr/include/c++/4.2/bits/stl_set.h:429: note: candidates are: typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::const_iterator std::set<_Key, _Compare, _Alloc>::find(const _Key&) [with _Key = nod, _Compare = std::less<nod>, _Alloc = std::allocator<nod>] /usr/include/c++/4.2/bits/stl_set.h:433: note: typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::const_iterator std::set<_Key, _Compare, _Alloc>::find(const _Key&) const [with _Key = nod, _Compare = std::less<nod>, _Alloc = std::allocator<nod>] user.cpp:30: error: expected primary-expression before '(' token user.cpp:34: error: expected `)' before 'int' user.cpp:36: error: expected `;' at end of input user.cpp:36: error: expected `}' at end of input user.cpp:36: error: expected `}' at end of input user.cpp:36: error: expected `}' at end of input