Compilare: main.cpp: In function 'int main()': main.cpp:23:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 23 | for (int k = 1; k < s.length(); k++) p[0] = p[0] * B0 % M0; | ~~^~~~~~~~~~~~