Compilare: user.cpp: In member function ‘node* trie::getPos(const string&)’: user.cpp:44:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < str.size (); ++i) ^ user.cpp: In member function ‘void trie::addWord(const string&)’: user.cpp:63:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < str.size (); ++i) ^ user.cpp: In member function ‘void trie::deleteWord(const string&)’: user.cpp:77:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (st->level == str.size ()) ^ user.cpp: In member function ‘int trie::query(const string&)’: user.cpp:93:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (st->level == str.size ()) ^ user.cpp: In function ‘int main()’: user.cpp:112:13: warning: unused variable ‘x’ [-Wunused-variable] int type, x; ^