Compilare: user.cpp: In function ‘int main()’: user.cpp:83: warning: operation on ‘l’ may be undefined user.cpp:83: warning: operation on ‘l’ may be undefined user.cpp:84: warning: operation on ‘l’ may be undefined user.cpp:84: warning: operation on ‘l’ may be undefined user.cpp:85: warning: operation on ‘l’ may be undefined user.cpp:85: warning: operation on ‘l’ may be undefined user.cpp:86: warning: operation on ‘l’ may be undefined user.cpp:86: warning: operation on ‘l’ may be undefined