It is not written in the statement explicitly, but the solution has to be non-precise. The epsilon can be determined only by random submissions.

It is possible to solve the problem 100% precisely, using only integers, but it will give WA 4.

Thank you!
I used EPS = 1e-2 and got WA #49
I used EPS = 1e-3 and got AC

There is this sentence in the problem statement: "The coordinates are accurate to 0.0001."
This makes me think EPS should be larger than 1e-4. How much larger? Hard to tell without submitting.

Also, this sentence makes me think that the coordinates are not precise, therefore a solution using only integers would be expected to fail.

One more thing: Since it's guaranteed that at least one solution always exists, I believe the only case where EPS = 1e-2 / EPS = 1e-3 can make a difference is the N = 2 case.