arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2104.08003cs.DScs.DMmath.CO
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图的内射边染色的复杂性及算法

Complexity and algorithms for injective edge-coloring in graphs

Florent Foucaud, Hervé Hocquard, Dimitri Lajou

摘要:

图$G$的单射$k$ -边着色是将颜色(即$\{1, \ldots , k\}$中的整数)分配给$G$的边,使得每个与第三条边的一个不同端点关联的任何两条边接收不同的颜色。确定这种$k$ -着色是否存在的问题称为k-内射边着色。我们证明了3-内射边染色是NP-完全的,即使对于无三角形的三次图、任意大围长的平面次三次图和围长为6的平面二部次三次图也是如此。4-对于三次图,内射边染色是NP-完全的。对于任何$k\geq 45$,我们证明了k-内射边着色保持NP-完全,即使是最大度至多$5\sqrt{3k}$的图。与这些否定的结果相反,我们证明了\InjPbName{k}是线性时间有界树宽图上可解的。此外,我们证明了围长至少为~16的所有平面二部次三图都是$3$ -边可注入着色的。此外,任何最大度至多为$\sqrt{k/2}$的图都是$k$ -边可注入着色的.

英文摘要:

An injective $k$-edge-coloring of a graph $G$ is an assignment of colors, i.e. integers in $\{1, \ldots , k\}$, to the edges of $G$ such that any two edges each incident with one distinct endpoint of a third edge, receive distinct colors. The problem of determining whether such a $k$-coloring exists is called k-INJECTIVE EDGE-COLORING. We show that 3-INJECTIVE EDGE-COLORING is NP-complete, even for triangle-free cubic graphs, planar subcubic graphs of arbitrarily large girth, and planar bipartite subcubic graphs of girth~6. 4-INJECTIVE EDGE-COLORING remains NP-complete for cubic graphs. For any $k\geq 45$, we show that k-INJECTIVE EDGE-COLORING remains NP-complete even for graphs of maximum degree at most $5\sqrt{3k}$. In contrast with these negative results, we show that \InjPbName{k} is linear-time solvable on graphs of bounded treewidth. Moreover, we show that all planar bipartite subcubic graphs of girth at least~16 are injectively $3$-edge-colorable. In addition, any graph of maximum degree at most $\sqrt{k/2}$ is injectively $k$-edge-colorable.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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