ACS algorithm applied to optimal layout of rectangular part

The optimal layout for rectangular part is a NP-complete combinatorial optimization problem.This optimal problem is re-presented by an AND/OR tree and then its optimal objective becomes to find the binary tree whose ratio of the area is maximum.To im-plement this kind of tree search using ant colony system algorithm,a number of artificial ants are distributed on the root of the AND/OR tree and communicate with one another through the pheromone trails which are a form of the long-term memory guiding the future explo-ration of the AND/OR tree,with which the optimal solution of the rectangular part optimal layout could be obtained.