fn shortest_path<'s, 'b>(
    start: Vertex<'s, 'b>,
    vertex_arena: &'b Bump,
    size_hint: usize,
    graph_limit: usize
) -> Result<Vec<(Edge, &'b Vertex<'s, 'b>)>, ExceededGraphLimit>
Expand description

Return the shortest route from the start to the end vertex.

The vec returned does not return the very last vertex. This is necessary because a route of N vertices only has N-1 edges.