Compilare: user.cpp: In function ‘T to_int(const std::string&)’: user.cpp:15: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:136: warning: comparison between signed and unsigned integer expressions user.cpp:139: warning: comparison between signed and unsigned integer expressions user.cpp:141: warning: comparison between signed and unsigned integer expressions user.cpp:143: warning: comparison between signed and unsigned integer expressions user.cpp: In member function ‘std::pair<char, T>& Bucket<T>::find_pos(char) [with T = Bucket<Bucket<int> >]’: user.cpp:131: instantiated from here user.cpp:72: warning: comparison between signed and unsigned integer expressions user.cpp: In member function ‘std::pair<char, T>& Bucket<T>::find_pos(char) [with T = Bucket<int>]’: user.cpp:131: instantiated from here user.cpp:72: warning: comparison between signed and unsigned integer expressions user.cpp: In member function ‘std::pair<char, T>& Bucket<T>::find_pos(char) [with T = int]’: user.cpp:131: instantiated from here user.cpp:72: warning: comparison between signed and unsigned integer expressions