dominikbraun / graph

A library for creating generic graph data structures and modifying, analyzing, and visualizing them.
https://graph.dominikbraun.io
Apache License 2.0
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implement bellman ford algorithm to find shortest path with negative weights #155

Open jhsinger-klotho opened 9 months ago

jhsinger-klotho commented 9 months ago

attempting to resolve #145

Implementing bellman ford algorithm for shortest path to include calculations of negative weights in a weighted graph.

The bellman ford algorithm will be run in ShortestPath when we have detected the algorithm is being run on a directed graph.

Algorithm will return an ErrTargetNotReachable if there is no path.

Because ShortestPath is a single source + target, performance lends itself to bellman ford (O(|V||E|)) in this scenario, so decided to implement that rather than johnsons algorithm (O(|V||E|+|V|^2log(|V|))).

Added unit tests to the bellman ford specific method and a single addition to shortestPath to test when the graph is directed