These are some links and papers on bidirectional A* variants. Nothing insightful at the moment. small lectureintroduces \(h_f(u) = \frac 12 (\pi_f(u) - \pi_r)\). Not found a paper yet.An Improved Bidirectional Heuristic Search Algorithm (Champeaux 1977)introduces a bidirectional variantBidirectional Heuristic Search Again (Champeaux 1983)fixes a bug in the above paperEfficient modified bidirectional A* algorithm for optimal route-findingDidn’t read closely yet.A new bidirectional algorithm ...
