A polynomial time solvable concave network flow problem

Abstract

Abstract We prove that the single‐source uncapacitated (SSU) version of the concave cost network flow problem, when all arcs except one have linear cost, is in the class P of problems solvable in time polynomial in the problem input length. This contrasts the corresponding result without network constraints, in which the problem is known to be NP‐hard [6]. © 1993 by John Wiley & Sons, Inc.