I think solutions like this are much too contrived. Cramming everything into a single line makes the solution unnecessarily hard to read and comprehend. Remember the Zen of Python: - Beautiful is better than ugly. - Explicit is better than implicit. - Simple is better than complex. - Complex More

Nice and compact formulation of Dijkstra's algorithm. Would be even more efficient if `closed` was an actual set instead of a list (searching for states using `x in closed` looks simple, but takes linear time). More

The basic idea behind the approach (either move directly from start to finish, or go through exactly one pair of boxes) is fine, but the solution does not scale to a large number of boxes, because then it must re-run the pathfinding algorithm for each pair of boxes on the map (and the pathfinding al More