Arboricity-Dependent Algorithms for Edge Coloring
Sayan Bhattacharya, Martín Costa, Nadav Panski, Shay Solomon
TL;DR
The paper studies dynamic edge coloring in graphs with bounded arboricity, showing a deterministic algorithm can maintain a $(Δ + O(α))$-edge coloring by exploiting a peeling-based decomposition and a discretized decomposition system to handle changing arboricity. The approach dynamically maintains local coloring constraints via ExtendColoring, with provable amortized bounds on update time and recolorings, and is adaptive to time-varying $Δ_t$ and $α_t$. For fixed arboricity, a warmup yields efficient recoloring with polylogarithmic update time; in general, the full algorithm achieves a $(Δ + O(α))$ coloring with near-constant recourse and polylogarithmic update time, particularly when $α leq Δ^{1-μ}$ for constant μ>0. These results advance dynamic graph algorithms by providing near-optimal additive colorings on sparse graphs (eg, planar, bounded-genus) under continual updates, with robust performance as graph parameters evolve.
Abstract
The problem of edge coloring has been extensively studied over the years. Recently, this problem has received significant attention in the dynamic setting, where we are given a dynamic graph evolving via a sequence of edge insertions and deletions and our objective is to maintain an edge coloring of the graph. Currently, it is not known whether it is possible to maintain a $(Δ+ O(Δ^{1 - μ}))$-edge coloring in $\tilde{O}(1)$ update time, for any constant $μ> 0$, where $Δ$ is the maximum degree of the graph. In this paper, we show how to efficiently maintain a $(Δ+ O(α))$-edge coloring in $\tilde O(1)$ amortized update time, where $α$ is the arboricty of the graph. Thus, we answer this question in the affirmative for graphs of sufficiently small arboricity.
