Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:52:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=1;j<=nivel[i].size();++j) ^ user.cpp:53:28: error: request for member ‘begin’ in ‘nivel[i].std::vector<_Tp, _Alloc>::operator[]<int, std::allocator<int> >(((std::vector<int>::size_type)j))’, which is of non-class type ‘__gnu_cxx::__alloc_traits<std::allocator<int> >::value_type {aka int}’ sort(nivel[i][j].begin()+1,nivel[i][j].end()+1); ^ user.cpp:53:50: error: request for member ‘end’ in ‘nivel[i].std::vector<_Tp, _Alloc>::operator[]<int, std::allocator<int> >(((std::vector<int>::size_type)j))’, which is of non-class type ‘__gnu_cxx::__alloc_traits<std::allocator<int> >::value_type {aka int}’ sort(nivel[i][j].begin()+1,nivel[i][j].end()+1); ^ user.cpp:55:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=1;j<=nivel[i].size();++j) ^ user.cpp:37:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nivele2.in", "r", stdin); ^ user.cpp:38:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nivele2.out", "w", stdout); ^ user.cpp:40:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:44:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^