Java - How to find a value from a hashmap that is the closest to a particular number?

Question

Hi I have a HashMap and also a function which returns a double value known as answer. I want to check which value in the Hash

Answer 1

The concept of 'closest' is not really meaningful for Hashed data structures. The primary goal of efficient hashing algorithms is collision avoidance, which is directly contrary to closeness. Either you have a collision, or not.

If you were asking this for an ordered key data structure (eg. TreeMap), the answer would be different.