We study the average performance of a simple greedy algorithm for finding a matching in a sparse random graph G , where c ) 0 is constant. The algorithm was first n, c r n w proposed by Karp and Sipser Proceedings of the Twenty-Second Annual IEEE Symposium on x Foundations of Computing, 1981, pp. 3
On large matchings and cycles in sparse random graphs
β Scribed by A.M Frieze
- Publisher
- Elsevier Science
- Year
- 1986
- Tongue
- English
- Weight
- 666 KB
- Volume
- 59
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
Let k be a fixed positive integer. A graph H has property Mk if it contains [Β½k] edge disjoint hamilton cycles plus a further edge disjoint matching which leaves at most one vertex isolated, if k is odd. Let p = c/n, where c is a large enough constant. We show that G,,p a.s. contains a vertex induced subgraph Ilk with property Mk and such that IV(Hk)I = (1 --(1 + e(c))ck-Xe-C/ (k -1)!)n, where e(c)--~O as c--~ oo. In particular this shows that for large c, G,,p a.s. contains a matching of size Β½(1 -(1 + e(c))e-C)n (k = 1) and a cycle of size (1 -(1 + e(c))ce-C)n (k = 2).
π SIMILAR VOLUMES
Select four perfect matchings of 2n vertices, independently at random. We find the asymptotic probability that each of the first and second matchings forms a Hamilton cycle with each of the third and fourth. This is generalised to embrace any fixed number of perfect matchings, where a prescribed set
The performance of the greedy coloring algorithm ''first fit'' on sparse random graphs G and on random trees is investigated. In each case, approximately n, c r n log log n colors are used, the exact number being concentrated almost surely on at 2 most two consecutive integers for a sparse random gr
Let G n,m,k denote the space of simple graphs with n vertices, m edges, and minimum degree at least k, each graph G being equiprobable. Let G have property A k , if G contains (k -1)/2 edge disjoint Hamilton cycles, and, if k is even, a further edge disjoint matching of size n/2 . We prove that, for
## Abstract For a graph __G__, let __a__(__G__) denote the maximum size of a subset of vertices that induces a forest. Suppose that __G__ is connected with __n__ vertices, __e__ edges, and maximum degree Ξ. Our results include: (a) if Ξββ€β3, and __G__ββ β__K__~4~, then __a__(__G__)ββ₯β__n__βββe/4βββ1