A Novel Parser Design Algorithm Based on Artificial Ants
  This article presents a unique design for a parser using the Ant Colony
Optimization algorithm. The paper implements the intuitive thought process of
human mind through the activities of artificial ants. The scheme presented here
uses a bottom-up approach and the parsing program can directly use ambiguous or
redundant grammars. We allocate a node corresponding to each production rule
present in the given grammar. Each node is connected to all other nodes
(representing other production rules), thereby establishing a completely
connected graph susceptible to the movement of artificial ants. Each ant tries
to modify this sentential form by the production rule present in the node and
upgrades its position until the sentential form reduces to the start symbol S.
Successful ants deposit pheromone on the links that they have traversed
through. Eventually, the optimum path is discovered by the links carrying
maximum amount of pheromone concentration. The design is simple, versatile,
robust and effective and obviates the calculation of the above mentioned sets
and precedence relation tables. Further advantages of our scheme lie in i)
ascertaining whether a given string belongs to the language represented by the
grammar, and ii) finding out the shortest possible path from the given string
to the start symbol S in case multiple routes exist.
