Some new results on minimum cycle covers are proved. As a consequence, it is obtained that the edges of a bridgeless graph G can be covered by cycles of total length at most |E(G)| + 25 24 (|V (G)| -1), and at most |E(G)| + |V (G)| -1 if G contains no circuit of length 8 or 12.
Minimum cycle coverings and integer flows
β Scribed by Cun-Quan Zhang
- Publisher
- John Wiley and Sons
- Year
- 1990
- Tongue
- English
- Weight
- 421 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Abstract
It was conjectured by Fan that if a graph G = (V,E) has a nowhereβzero 3βflow, then G can be covered by two even subgraphs of total size at most |V| + |E| β 3. This conjecture is proved in this paper. It is also proved in this paper that the optimum solution of the Chinese postman problem and the solution of minimum cycle covering problem are equivalent for any graph admitting a nowhereβzero 4βflow.
π SIMILAR VOLUMES
A k-flow is an assignment of edge directions and integer weights in the range 1, ..., k -1 to the edges of an undirected graph so that at each vertex the flow in is equal to the flow out. This paper gives a polynomial algorithm for finding a 6-flow that applies uniformly to each graph. The algorithm
## Abstract Let __G__ be a graph of order __n__ β₯ 5__k__ + 2, where __k__ is a positive integer. Suppose that the minimum degree of __G__ is at least β(__n__ + __k__)/2β. We show that __G__ contains __k__ pentagons and a path such that they are vertexβdisjoint and cover all the vertices of __G__. M
In this article, we show that for any simple, bridgeless graph G on n vertices, there is a family C of at most n-1 cycles which cover the edges of G at least twice. A similar, dual result is also proven for cocycles namely: for any loopless graph G on n vertices and edges having cogirth g \* β₯ 3 and