Compilare: user.c: In function ‘main’: user.c:10:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("pba.in","r",stdin); ^ user.c:11:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("pba.out","w",stdout); ^ user.c:13:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.c:16:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld",&v[i]); ^ user.c:22:9: warning: ‘j’ may be used uninitialized in this function [-Wmaybe-uninitialized] v[j]=-1; ^