Compilare: main.cpp: In function 'int main()': main.cpp:29:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 29 | for (int i = 1; i <= s.size(); i++) | ~~^~~~~~~~~~~ main.cpp:32:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 32 | if (i == s.size()) | ~~^~~~~~~~~~~