Compilare: main.cpp: In function 'void CryptMessage(std::string)': main.cpp:14:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 14 | while (index != text.length() + 1) | ~~~~~~^~~~~~~~~~~~~~~~~~~~