Given one endpoint of diameter and diameter length of a circle, how to find the other end point of diameter.?

Question

I am trying to solve a coding question in which I need to get the endpoint of diameter, given is one end point and diameter length.

(0,1) is point and 1 is diameter of circle.

Answer 1

Your target can be found in the circle $x^2 + (y - 1)^2 = 1$. But there are infinitely many.