Tromino tilings with pegs via flow networks.

Akagi, Javier T. - Canale, Eduardo A. - Villagra, Marcos

Resumen:

A tromino tiling problem is a packing puzzle where we are given a region of connected lattice squares and we want to decide whether there exists a tiling of the region using trominoes with the shape of an L. In this work we study a slight variation of the tromino tiling problem where some positions of the region have pegs and each tromino comes with a hole that can only be placed on top of the pegs. We present a characterization of this tiling problem with pegs using flow networks and show that (i) there exists a linear-time parsimonious reduction to the maximum-flow problem, and (ii) counting the number of such tilings can be done in linear-time. The proofs of both results contain algorithms that can then be used to decide the tiling of a region with pegs in O(n) time.

Detalles Bibliográficos
2021
Tromino tilings
Linear-time reduction
Parsimonious reduction
Maximum-flow
Bipartite matchings
Inglés
Universidad de la República
COLIBRI
https://hdl.handle.net/20.500.12008/50523
Acceso abierto
Licencia Creative Commons Atribución - No Comercial - Sin Derivadas (CC - By-NC-ND 4.0)