Compilare: main.cpp: In function 'int main()': main.cpp:16:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 16 | for(int i = 0; i<init.size(); i++) | ~^~~~~~~~~~~~ main.cpp:18:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 18 | if(i == init.size() - 1) | ~~^~~~~~~~~~~~~~~~~~