期刊名称:Electronic Colloquium on Computational Complexity
印刷版ISSN:1433-8092
出版年度:2021
卷号:21
语种:English
出版社:Universität Trier, Lehrstuhl für Theoretische Computer-Forschung
摘要:Since they were first introduced by Schulman (STOC 1993), the construction of tree codes remained an elusive open problem. The state-of-the-art construction by Cohen, Haeupler and Schulman (STOC 2018) has constant distance and (logn)e colors for some constant e1 that depends on the distance, where n is the depth of the tree. Insisting on a constant number of colors at the expense of having vanishing distance, Gelles, Haeupler, Kol, Ron-Zewi, and Wigderson (SODA 2016) constructed a distance (1logn) tree code. In this work we improve upon these prior works and construct a distance- tree code with (logn)O() colors. This is the first construction of a constant distance tree code with sub-logarithmic number of colors. Moreover, as a direct corollary we obtain a tree code with a constant number of colors and distance 1(loglogn)2 , exponentially improving upon the above-mentioned work by Gelles et al.