This is the Stanford Graph Base, which is a general purpose
connected graph utility suite by Don Knuth, programming God.

I've included it here because of the "ladder" demonstration
program included with the suite.  It generates Lewis Carroll
doublets (aka word ladder aka word golf) using a breadth-first
graph traversal.

This is basically the same algorithm as in ../ladder/ but
using a general purpose package instead of one-off code.  It may
turn out to be a useful tool for word game programmers.