[nesrgbpq] maze of thickness 2

create a maze within a (2 x A x B x ...) slab of 2 layers of cubes or hypercubes.  every hypercube touches the outside.  after determining the longest shortest path (graph diameter), the endpoints are therefore guaranteed to be on the edge of the maze, suitable for entrance and exit.  previously, finding the longest path between edge nodes when not all nodes are on a edge.

vaguely similar is a 2D maze whose entrance and exit are in the middle but accessible by 3D bridges going over the maze.