Compilare: user.cpp: In function ‘int main()’: user.cpp:41:12: warning: unused variable ‘l’ [-Wunused-variable] ll l = v.begin()->x, r = v.rbegin()->x; ^ user.cpp:28:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:32:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld", &x); ^