Compilare: user.cpp: In function ‘int main()’: user.cpp:185: warning: deprecated conversion from string constant to ‘char*’ user.cpp:185: warning: deprecated conversion from string constant to ‘char*’ user.cpp: In member function ‘void double_hash<T>::operator+(T) [with T = int]’: user.cpp:187: instantiated from here user.cpp:114: warning: unused variable ‘sem’