An Efficient Algorithm for the Min-Sum Arborescence Problem on Complete Digraphs

An efficient algorithm for the solution of the Min-Sum Arborescence Problem with fixed root-vertex in complete digraphs is presented. The algorithm is based on the well-known Edmonds method. The new approach makes use of simple data structures leading to improvements affecting both computing times and memory requirements. Further improvements are obtained by using a new algorithm based on the solution of a sparse problem. The linear programming reduced costs associated with the arcs are also computed. A FORTRAN implementation is described; the corresponding code is available, on request, from the authors. Extensive computational results on both real-world and random instances are given, showing the effectiveness of the proposed algorithms.

INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.