Compilare: user.cpp: In function ‘uint8_t get(const string&, int)’: user.cpp:7:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] return (poz >= num.size()) ? 0 : num[poz]; } ^ user.cpp: In function ‘void set(std::string&, int, uint8_t)’: user.cpp:10:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(num.size() <= poz){ ^ user.cpp: In function ‘void add(std::string&, int)’: user.cpp:25:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < num.size() || in_minte != 0; ++i){ ^