Compilare: main.cpp: In function 'void add(Trie*, std::string, int)': main.cpp:26:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 26 | if (pos == s.size()) { | ~~~~^~~~~~~~~~~ main.cpp: In function 'void del(Trie*, std::string, int)': main.cpp:38:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 38 | if (pos == s.size()) { | ~~~~^~~~~~~~~~~ main.cpp: In function 'int cnt(Trie*, std::string, int)': main.cpp:48:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 48 | if (pos == s.size()) | ~~~~^~~~~~~~~~~ main.cpp: In function 'int pref(Trie*, std::string, int)': main.cpp:57:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 57 | if (pos == s.size()) | ~~~~^~~~~~~~~~~