English

Bijection: Parking-like structures and Tree-like structures

Combinatorics 2015-03-17 v1

Abstract

We recall the occupancy problem introduced by Konheim & Weiss in 1966 and we consider parking functions as hash maps. Each car cic_i prefers parking space pip_i (the hash map cipic_i \mapsto p_i with cic_i is a key and pip_i an index into an array), if pip_i is occupied then cic_i the next available parking space (the hash table implementation using an open addressing strategy). This paper considers some others hash table implementations like hash tables with linked lists (with parking functions as hash maps). Using the Species Theory, we enumerate by Lagrange inversion those hash tables structures via a bijection with tree-like structures. This bijection provides a generalization of the Foata-Riordan bijection between parking functions and (forests of) rooted trees. Finally we show the number of hash tables with linked lists on a set of keys of cardinality nn is n!Cnn!C_n, so the number of labeled binary trees with nn nodes.

Keywords

Cite

@article{arxiv.1503.04245,
  title  = {Bijection: Parking-like structures and Tree-like structures},
  author = {Jean-Baptiste Priez},
  journal= {arXiv preprint arXiv:1503.04245},
  year   = {2015}
}
R2 v1 2026-06-22T08:52:50.216Z