Simple implementation of deletion from open-address hash table

TL;DR

This paper presents a simple alternative method for deleting keys in open-address hash tables that avoids using the traditional 'deleted' mark, with an implementation in Java.

Contribution

It introduces a novel deletion method for open-address hash tables that simplifies implementation by not using the 'deleted' marker.

Findings

The method simplifies deletion process in open-address hash tables.

Implementation in Java demonstrates practical applicability.

Avoids issues caused by 'deleted' markers in search correctness.

Abstract

Deletion from open-address hash table is not so easy as deletion from chained hash table, because in open-address table we can't simply mark a slot containing deleted key as empty. Search for keys may become incorrect. The classical method to implement deletion is to mark slots in hash table by three values: "free", "busy", "deleted". That method is easy to implement, but there are some disadvantages. In this article we consider alternative method of deletion keys, where we avoid using the mark "deleted". The article contains the implementation of the method in Java.