Compilare: main.cpp: In function 'void insert(trie*, std::string&, int)': main.cpp:20:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 20 | if( i == s.size() ){ | ~~^~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:73:33: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 73 | while( r.size() < k ){ | ~~~~~~~~~^~~