A note on permutation flow shop problem

In this paper we present two approximation algorithms for the permutation flow shop problem with makespan objective. The first algorithm has an absolute performance guarantee, the second one is an O(√m log m)-approximation algorithm. The last result is almost best possible approximation algorithm which can be obtained using the trivial lower bound (maximum of the maximum machine load and the maximum job length) (Potts, Shmoys, and Williamson, 1991).