Eroare de compilare: user.cpp: In function ‘bool is_forest(std::vector<std::vector<int> >&)’: user.cpp:20:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v.size(); ++i) ~~^~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:52:58: error: no matching function for call to ‘find(std::vector<int>::iterator, std::vector<int>::iterator, int&)’ v[y].erase(find(begin(v[y]), end(v[y]), x)); } } ^ In file included from /usr/include/c++/6/bits/locale_facets.h:48:0, from /usr/include/c++/6/bits/basic_ios.h:37, from /usr/include/c++/6/ios:44, from /usr/include/c++/6/istream:38, from /usr/include/c++/6/fstream:38, from user.cpp:1: /usr/include/c++/6/bits/streambuf_iterator.h:369:5: note: candidate: template<class _CharT2> typename __gnu_cxx::__enable_if<std::__is_char<_CharT2>::__value, std::istreambuf_iterator<_CharT> >::__type std::find(std::istreambuf_iterator<_CharT>, std::istreambuf_iterator<_CharT>, const _CharT2&) find(istreambuf_iterator<_CharT> __first, ^~~~ /usr/include/c++/6/bits/streambuf_iterator.h:369:5: note: template argument deduction/substitution failed: user.cpp:52:58: note: ‘__gnu_cxx::__normal_iterator<int*, std::vector<int> >’ is not derived from ‘std::istreambuf_iterator<_CharT>’ v[y].erase(find(begin(v[y]), end(v[y]), x)); } } ^ user.cpp:55:36: error: ‘all_of’ was not declared in this scope return x.size() <= 2; }) << '\n'; } ^