Compilare: user.cpp: In member function ‘char stiva::pop()’: user.cpp:65:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:76:9: warning: unused variable ‘k’ [-Wunused-variable] int k; ^ user.cpp: In member function ‘char stiva::peek()’: user.cpp:41:1: warning: control reaches end of non-void function [-Wreturn-type] } ^