Compilare: user.cpp: In function ‘int main()’: user.cpp:20: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void read()’: user.cpp:45: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘std::vector<int, std::allocator<int> > impartire(std::vector<int, std::allocator<int> >)’: user.cpp:71: warning: comparison between signed and unsigned integer expressions