Compilare: user.c: In function ‘main’: user.c:14:5: warning: implicit declaration of function ‘qsort’ [-Wimplicit-function-declaration] r=v[1],v[1]=v[p],v[p]=r,qsort(&v[2],sizeof(v)/sizeof(P),sizeof(P),C),s[++t]=1; ^ user.c:11:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("infasuratoare.in","r",stdin),freopen("infasuratoare.out","w",stdout),scanf("%d",&n); ^ user.c:11:50: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("infasuratoare.in","r",stdin),freopen("infasuratoare.out","w",stdout),scanf("%d",&n); ^ user.c:11:88: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] freopen("infasuratoare.in","r",stdin),freopen("infasuratoare.out","w",stdout),scanf("%d",&n); ^ user.c:13:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf%lf",&v[i].x,&v[i].y),p=v[i].x<v[p].x||(v[i].x==v[p].x&&v[i].y<v[p].y)?i:p; ^