Compilare: main.cpp: In static member function 'static void trie::add_word(std::__cxx11::string, trie*, int)': main.cpp:18:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz == s.size()) { ~~~~^~~~~~~~~~~ main.cpp: In static member function 'static bool trie::erase_word(std::__cxx11::string, trie*, int)': main.cpp:31:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz == s.size()) { ~~~~^~~~~~~~~~~ main.cpp: In static member function 'static int trie::find_fr(std::__cxx11::string, trie*, int)': main.cpp:53:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz == s.size()) ~~~~^~~~~~~~~~~ main.cpp: In static member function 'static int trie::find_prefix(std::__cxx11::string, trie*, int)': main.cpp:60:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz == s.size()) ~~~~^~~~~~~~~~~