Single-Source Shortest Paths with Negative Real Weights in Õ(mn8/9) Time

This paper presents a randomized algorithm for single-source shortest paths on directed graphs with real (both positive and negative) edge weights. Given an input graph with n vertices and m edges, the algorithm completes in Õ(mn8/9) time with high probability. For real-weighted graphs, this result constitutes the first asymptotic improvement over the classic O(mn)-time algorithm variously attributed to Shimbel, Bellman, Ford, and Moore.