Find K nearest Points to Point P in 2-dimensional plane

Question

Source: AMAZON INTERVIEW QUESTION

Given a point P and other N points in two dimensional space, find K points

Answer 1

For just a single query...

Maintain a heap of size k.

For each point, calculate the distance to the point P. Insert that distance into the heap and delete the maximum from the heap if the size of the heap is greater than k.

Running time: O(n log k)