Compilare: user.cpp: In function ‘int main()’: user.cpp:105:9: warning: unused variable ‘val’ [-Wunused-variable] int val; ^~~ user.cpp: In member function ‘T Deque<T>::Back() [with T = int]’: user.cpp:85:5: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In member function ‘T Deque<T>::Front() [with T = int]’: user.cpp:80:5: warning: control reaches end of non-void function [-Wreturn-type] } ^