Compilare: user.c: In function ‘main’: user.c:17:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("reuniune.in","r",stdin),freopen("reuniune.out","w",stdout); ^ user.c:17:42: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("reuniune.in","r",stdin),freopen("reuniune.out","w",stdout); ^ user.c:19:8: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld%lld%lld%lld",&a[i].x,&a[i].y,&b[i].x,&b[i].y),r[i].c.x=a[i].x,r[i].c.y=b[i].y,r[i].d.x=b[i].x,r[i].d.y=a[i].y; ^