Compilare: main.cpp: In function 'void Insert(Trie*, std::__cxx11::string)': main.cpp:17:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<s.size();i++) ~^~~~~~~~~ main.cpp: In function 'int Find(Trie*, std::__cxx11::string)': main.cpp:71:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<s.size();i++) ~^~~~~~~~~ main.cpp: In function 'int LongestPrefix(Trie*, std::__cxx11::string)': main.cpp:88:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<s.size();i++) ~^~~~~~~~~