Almost all k-colorable graphs are easy to color
نویسندگان
چکیده
منابع مشابه
Almost All k-Colorable Graphs are Easy to Color
We describe a simple and eecient heuristic algorithm for the graph coloring problem and show that for all k 1, it nds an optimal coloring for almost all k-colorable graphs. We also show that an algorithm proposed by Br elaz and justiied on experimental grounds optimally colors almost all k-colorable graphs. EEcient implementations of both algorithms are given. The rst one runs in O(n+m log k) t...
متن کاملWhy almost all satisfiable k-CNF formulas are easy
Finding a satisfying assignment for a k-CNF formula (k ≥ 3), assuming such exists, is a notoriously hard problem. In this work we consider the uniform distribution over satisfiable k-CNF formulas with a linear number of clauses (clause-variable ratio greater than some constant). We rigorously analyze the structure of the space of satisfying assignments of a random formula in that distribution, ...
متن کاملWhy almost all k-CNF formulas are easy
Finding a satisfying assignment for a k-CNF formula (k ≥ 3), assuming such exists, is a notoriously hard problem. In this work we consider the uniform distribution over satisfiable k-CNF formulas with a linear number of clauses (clause-variable ratio greater than some constant). We rigorously analyze the structure of the space of satisfying assignments of a random formula in that distribution, ...
متن کاملAlmost all graphs with 2.522 n edges are not 3-colorable
We prove that for c ≥ 2.522 a random graph with n vertices and m = cn edges is not 3-colorable with probability 1− o(1). Similar bounds for non-k-colorability are given for k > 3. 1991 Mathematics Subject Classification: Primary 05C80; Secondary 05C15.
متن کاملThe Parallel Maxxow Problem Is Easy for Almost All Graphs
We present a novel algorithm for the integer maxxow problem. The algorithm is designed for a PRAM CREW with n 2 processing units. For almost all (in a strong sense) graphs of a number of common classes of random graphs, it nds a maxxow in O((log C + log 4 n) log n= log(m=n)) time. Here C is the average edge capacity and m the (expected) number of edges. The same time bound holds for the average...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Algorithms
سال: 1988
ISSN: 0196-6774
DOI: 10.1016/0196-6774(88)90005-3