Compilare: user.c: In function ‘main’: user.c:15:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("reuniune.in","r",stdin),freopen("reuniune.out","w",stdout),scanf("%d%d%d%d",&a.x1,&a.y1,&a.x2,&a.y2), ^ user.c:15:45: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("reuniune.in","r",stdin),freopen("reuniune.out","w",stdout),scanf("%d%d%d%d",&a.x1,&a.y1,&a.x2,&a.y2), ^ user.c:15:78: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("reuniune.in","r",stdin),freopen("reuniune.out","w",stdout),scanf("%d%d%d%d",&a.x1,&a.y1,&a.x2,&a.y2), ^ user.c:16:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&b.x1,&b.y1,&b.x2,&b.y2),scanf("%d%d%d%d",&c.x1,&c.y1,&c.x2,&c.y2),x=R(a,b),y=R(a,c),z=R(b,c),t=R(x,c); ^ user.c:16:52: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&b.x1,&b.y1,&b.x2,&b.y2),scanf("%d%d%d%d",&c.x1,&c.y1,&c.x2,&c.y2),x=R(a,b),y=R(a,c),z=R(b,c),t=R(x,c); ^