Compilare: main.cpp: In function 'void manacher(std::string&, std::vector<long long int>&)': main.cpp:97:44: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 97 | while(0<=i-len[i]&&i+len[i]<s.size()&&s[i-len[i]]==s[i+len[i]])len[i]++; | ~~~~~~~~^~~~~~~~~