  It has been shown by Alon et al. that the so-called 'all-pairs shortest-path'
problem can be solved in O((MV)^2.688 * log^3(V)) for graphs with V vertices,
with integer distances bounded by M. We solve the more general problem for
graphs in R (assuming no negative cycles), with expected-case running time
O(V^2.5 * log(V)). While our result appears to violate the Omega(V^3)
requirement of "Funny Matrix Multiplication" (due to Kerr), we find that it has
a sub-cubic expected time solution subject to reasonable conditions on the data
distribution. The expected time solution arises when certain sub-problems are
uncorrelated, though we can do better/worse than the expected-case under
positive/negative correlation (respectively). Whether we observe
positive/negative correlation depends on the statistics of the graph in
question. In practice, our algorithm is significantly faster than
Floyd-Warshall, even for dense graphs.
