Compilare: user.c: In function ‘main’: user.c:49:10: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("beri.in", "r", stdin); ^ user.c:50:10: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("beri.out", "w", stdout); ^ user.c:52:8: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld %lld", &n, &k); ^ user.c:54:8: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld %lld %lld %lld", &a[0], &x, &y, &z); ^