Compilare: user.cpp: In function `int main()': user.cpp:10: warning: format argument is not a pointer (arg 2) user.cpp:13: warning: int format, long unsigned int arg (arg 2) user.cpp:29: warning: int format, long unsigned int arg (arg 2) user.cpp:6: warning: unused variable `int ok' user.cpp:6: warning: `int n' might be used uninitialized in this function user.cpp:31:2: warning: no newline at end of file