SixArm

#!/usr/bin/env ruby
#
# Two words are "directly connected" if one word can transform into the other by any of:
#   * substitution of one character for another, e.g. "tan" => "ton"
#   * insertion of one character, e.g. "tan" => "than"
#   * deletion of one character, e.g. "tan" => "an"
#
# Two words are "connected" if applying the rules above repeatedly can directly connect words:
#   * e.g. "tan" => "ton" => "tone" => "one" => "on"
#   * e.g. "tan" => "an" => "in" => "pin" => "pink"