Compilare: user.cpp: In function ‘void update(int, Trie*)’: user.cpp:22:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (poz == s.size()) ^ user.cpp: In function ‘int query(int, Trie*)’: user.cpp:35:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( poz == s.size()) ^ user.cpp: In function ‘int main()’: user.cpp:77:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int ii = 0; ii < s.size(); ii++) ^