Compilare: main.cpp: In function 'int main()': main.cpp:19:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 19 | for (int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~ main.cpp:33:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 33 | for (int i = 2; i <= s.size() + 1; i++) | ~~^~~~~~~~~~~~~~~ main.cpp:18:9: warning: unused variable 'ij' [-Wunused-variable] 18 | int ij = s.size() + 1, jj = 1; | ^~