Compilare: main.cpp: In function 'int getNumber(int&, std::__cxx11::string)': main.cpp:17:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(p < s.size() && '0' <= s[p] && s[p] <= '9') ~~^~~~~~~~~~ main.cpp: In function 'int evaluate(std::__cxx11::string, int, int)': main.cpp:36:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < s.size()) { ~~^~~~~~~~~~ main.cpp:39:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i == s.size()) { ~~^~~~~~~~~~~