Compilare: main.cpp: In function 'int main()': main.cpp:49:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 49 | for(int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~ main.cpp:53:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 53 | while(i < s.size() && isdigit(s[i])) | ~~^~~~~~~~~~