From the NannyMUD documentation

LAST CHANGE

2000-12-12

FUNCTION

NAME
        _find_shortest_path - Width-first search of numeric database.


SYNTAX
        mixed * _find_shortest_path(mixed *database,
                                    int from, int to, int max_nr)

DESCRIPTION
        Given a database, this very costly efun finds the shortest path
        between two points in the database. The arguments are:

        database        An array of arrays of integers. The first element of
                        the database holds an array with indexes for other
                        elements to which the first element is considered
                        connected.
        from            The index of the point where you want to start.
        to              The index of the point where you want to end.
        max             The largest number of steps you accept. Setting this to
                        a very large number will ensure an exhaustive search of
                        the database for possible paths; beware the case of NO
                        connection (in which case all of the database is
                        searched).


NOTE
        This efun has the potential to be so costly that its use is
        restricted; it needs approval.