Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:11: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:12: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result In file included from /usr/include/c++/4.4/set:60, from user.cpp:2: /usr/include/c++/4.4/bits/stl_tree.h: In member function ‘std::_Rb_tree_iterator<_Val> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::find(const _Key&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’: /usr/include/c++/4.4/bits/stl_set.h:548: instantiated from ‘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 = int, _Compare = int, _Alloc = std::allocator<int>]’ user.cpp:22: instantiated from here /usr/include/c++/4.4/bits/stl_tree.h:1424: error: ‘((std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >*)this)->std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_M_impl.std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_Rb_tree_impl<int, true>::_M_key_compare’ cannot be used as a function /usr/include/c++/4.4/bits/stl_tree.h: In member function ‘std::pair<typename std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::iterator, bool> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_insert_unique(const _Val&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’: /usr/include/c++/4.4/bits/stl_set.h:411: instantiated from ‘std::pair<typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::const_iterator, bool> std::set<_Key, _Compare, _Alloc>::insert(const _Key&) [with _Key = int, _Compare = int, _Alloc = std::allocator<int>]’ user.cpp:22: instantiated from here /usr/include/c++/4.4/bits/stl_tree.h:1170: error: ‘((std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >*)this)->std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_M_impl.std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_Rb_tree_impl<int, true>::_M_key_compare’ cannot be used as a function /usr/include/c++/4.4/bits/stl_set.h:411: instantiated from ‘std::pair<typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::const_iterator, bool> std::set<_Key, _Compare, _Alloc>::insert(const _Key&) [with _Key = int, _Compare = int, _Alloc = std::allocator<int>]’ user.cpp:22: instantiated from here /usr/include/c++/4.4/bits/stl_tree.h:1181: error: ‘((std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >*)this)->std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_M_impl.std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_Rb_tree_impl<int, true>::_M_key_compare’ cannot be used as a function /usr/include/c++/4.4/bits/stl_tree.h: In member function ‘std::_Rb_tree_iterator<_Val> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_lower_bound(std::_Rb_tree_node<_Val>*, std::_Rb_tree_node<_Val>*, const _Key&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’: /usr/include/c++/4.4/bits/stl_tree.h:1421: instantiated from ‘std::_Rb_tree_iterator<_Val> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::find(const _Key&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’ /usr/include/c++/4.4/bits/stl_set.h:548: instantiated from ‘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 = int, _Compare = int, _Alloc = std::allocator<int>]’ user.cpp:22: instantiated from here /usr/include/c++/4.4/bits/stl_tree.h:986: error: ‘((std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >*)this)->std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_M_impl.std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_Rb_tree_impl<int, true>::_M_key_compare’ cannot be used as a function /usr/include/c++/4.4/bits/stl_tree.h: In member function ‘std::_Rb_tree_iterator<_Val> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_insert_(const std::_Rb_tree_node_base*, const std::_Rb_tree_node_base*, const _Val&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’: /usr/include/c++/4.4/bits/stl_tree.h:1177: instantiated from ‘std::pair<typename std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::iterator, bool> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_insert_unique(const _Val&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’ /usr/include/c++/4.4/bits/stl_set.h:411: instantiated from ‘std::pair<typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::const_iterator, bool> std::set<_Key, _Compare, _Alloc>::insert(const _Key&) [with _Key = int, _Compare = int, _Alloc = std::allocator<int>]’ user.cpp:22: instantiated from here /usr/include/c++/4.4/bits/stl_tree.h:879: error: ‘((std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >*)this)->std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_M_impl.std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_Rb_tree_impl<int, true>::_M_key_compare’ cannot be used as a function /usr/include/c++/4.4/bits/stl_tree.h: In member function ‘std::pair<typename std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::iterator, typename std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::iterator> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::equal_range(const _Key&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’: /usr/include/c++/4.4/bits/stl_tree.h:1372: instantiated from ‘size_t std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::erase(const _Key&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’ /usr/include/c++/4.4/bits/stl_set.h:491: instantiated from ‘typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::size_type std::set<_Key, _Compare, _Alloc>::erase(const _Key&) [with _Key = int, _Compare = int, _Alloc = std::allocator<int>]’ user.cpp:23: instantiated from here /usr/include/c++/4.4/bits/stl_tree.h:1054: error: ‘((std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >*)this)->std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_M_impl.std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_Rb_tree_impl<int, true>::_M_key_compare’ cannot be used as a function /usr/include/c++/4.4/bits/stl_tree.h:1056: error: ‘((std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >*)this)->std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_M_impl.std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_Rb_tree_impl<int, true>::_M_key_compare’ cannot be used as a function /usr/include/c++/4.4/bits/stl_tree.h: In member function ‘std::_Rb_tree_iterator<_Val> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_upper_bound(std::_Rb_tree_node<_Val>*, std::_Rb_tree_node<_Val>*, const _Key&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’: /usr/include/c++/4.4/bits/stl_tree.h:1065: instantiated from ‘std::pair<typename std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::iterator, typename std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::iterator> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::equal_range(const _Key&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’ /usr/include/c++/4.4/bits/stl_tree.h:1372: instantiated from ‘size_t std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::erase(const _Key&) [with _Key = int, _Val = int, _KeyOfValue = std::_Identity<int>, _Compare = int, _Alloc = std::allocator<int>]’ /usr/include/c++/4.4/bits/stl_set.h:491: instantiated from ‘typename std::_Rb_tree<_Key, _Key, std::_Identity<_Key>, _Compare, typename _Alloc::rebind<_Key>::other>::size_type std::set<_Key, _Compare, _Alloc>::erase(const _Key&) [with _Key = int, _Compare = int, _Alloc = std::allocator<int>]’ user.cpp:23: instantiated from here /usr/include/c++/4.4/bits/stl_tree.h:1018: error: ‘((std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >*)this)->std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_M_impl.std::_Rb_tree<int, int, std::_Identity<int>, int, std::allocator<int> >::_Rb_tree_impl<int, true>::_M_key_compare’ cannot be used as a function