Monte Carlo simulation that calculates the average shortest path in a graph

Program will be generate random graph with edge density as a parameter and distance range as a parameter.
So a graph whose density is 0.1 would have 10% of its edges picked at random and its edge distance would
be selected at random from the distance range. The procedure should run through all possible undirected edges,
say (i,j) and place the edge in the graph if a random probability calculation is less than the density.
Compute for a set of randomly generated graphs an average shortest path.