Compilare: main.cpp: In member function 'void Trie::ins(std::string&)': main.cpp:40:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 40 | while (idx < s.size()) | ~~~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:90:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 90 | for (int i = 0; i < s.size(); ++i) | ~~^~~~~~~~~~