pls, give me some tests

I've too have this problem:)

Well, I had this problem, too.
This is caused by a small bug, that is very silly.

You must have written something like this:

if (xA * xA + yA * yA < R * R / 2)
cout<<"NO"<<endl;

However, the solution should be like this:

if ((xA * xA + yA * yA) * 2 < R * R)
cout<<"NO"<<endl;

What a stupid mistake!

Good luck :)