In the past few years, new very successful bidirectional heuristic search algorithms have
been proposed. Their key novelty is a lower bound on the cost of a solution that includes …

The state of the art in bidirectional search has changed significantly a very short time period;
we now can answer questions about unidirectional and bidirectional search that until very …

Recent work in bidirectional heuristic search characterize pairs of nodes from which at least
one node must be expanded in order to ensure optimality of solutions. We use these …

Most recent theoretical and algorithmic work in bidirectional heuristic search (BiHS) used
front-to-end (F2E) heuristics that estimate the distance to the start and goal states. In this …

We present MM, the first bidirectional heuristic search algorithm whose forward and
backward searches are guaranteed to''meet in the middle'', ie never expand a node beyond …

The assessment of bidirectional heuristic search has been incorrect since it was first
published more than a quarter of a century ago. For quite a long time, this search strategy …

It is well-known that any admissible unidirectional heuristic search algorithm must expand all
states whose $ f $-value is smaller than the optimal solution cost when using a consistent …

Bidirectional search algorithms interleave two separate searches, a normal search forward
from the start state, and a search backward from the goal. It is well known that adding a …

Bidirectional search algorithms interleave a search forward from the start state (start) and a
search backward (ie using reverse operators) from the goal state (goal). We say that the two …

We introduce a new bidirectional search algorithm, Single-Frontier Bidirectional Search
(SFBDS). Unlike traditional BDS which keeps two frontiers, SFBDS uses a single frontier. At …