Parallel Processing Method of Combinatorial Problem Solving Based on Implicit Stochastic Divide-and-Conquer*

A method of solving combinatorial problems, such as the N queens problem or graph coloring problems using independent parallel processes, is proposed. This method is stochastic (or randomized). Problems are decomposed for parallel processing implicitly and stochastically. This method is based on CCM, which is a computational model proposed by the author. A program consists of production rules and local evaluation functions in CCM. Each process uses the same set of rules and functions, and it may use the same set of initial data. However, the performance is approximately in proportion to the number of processors in average in certain cases. The theoretical reason of this linear acceleration is explained, and several results of experiments are also shown.