I’m supposed to be doing the final edits on the journal version of this old paper of mine (jointly with Greg Sorkin and David Gamarnik), but I’ve thought of a way to procrastinate.
Instead of checking the proofs that the length of the shortest path in my weigthed width-2 strip is 
from pylab import *
from networkx import *
G = Graph()
for u, v in grid_2d_graph(100, 2).edges():
G.add_edge(u, v, weight=rand() < .5)
wt, p = bidirectional_dijkstra(G, (0,0), (99,1))
Healthy Algorithms 