Compilare: user.cpp: In function ‘std::vector<int, std::allocator<int> > read()’: user.cpp:14: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int main()’: user.cpp:44: warning: comparison between signed and unsigned integer expressions user.cpp:43: warning: unused variable ‘a’