Wed 08 Jan 2020

Finding unique items - hash vs sort?

A while back, I was trying to speed up some code which finds unique items in a collection. For example, transforming "AABBADCAB" => "ABDC". There are two ways to do this efficiently - one is based on sorting, the other based on hashing. So, which is faster? I couldn't find the answer, so I ran some experiments and here are the results.

Source: Hash vs Sort.