Compilare: user.c: In function ‘main’: user.c:6:24: warning: unused variable ‘e’ [-Wunused-variable] int i,j,a,b,nr,div,e,ct; ^ user.c:6:20: warning: unused variable ‘div’ [-Wunused-variable] int i,j,a,b,nr,div,e,ct; ^ user.c:7:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("nasa.in","r",stdin); ^ user.c:8:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("nasa.out","w",stdout); ^ user.c:9:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^ user.c:13:14: warning: ‘nr’ may be used uninitialized in this function [-Wmaybe-uninitialized] for(j=nr/(i*i); (long long)i*i*j<=b; j++) ^