Traveling-salesman type competition and simultaneous move search algorithm

In this paper, we study a traveling-salesman type competition in which two salesmen independently visit n cities and compete with each other for the number of visiting cities. Similar competitions can be widely found in the real world such as in selling competitions and in the competitive gathering of scrap materials. The competition is modeled as a game such that players travel around various objects distributed in a given area and compete with each other in collecting the objects. In this game model, players move simultaneously, that is, not alternately. We present a novel scheduling algorithm suitable for the game model in which a move toward an object along the shortest path is taken as the basic move, and the move is stopped halfway when the opponent has the advantage. In the algorithm, the moves of the players can be dealt with quasi-alternately. However, a player can make several consecutive moves, and a move already made can be aborted. A position evaluation method based on the concept of territory is also presented. A simulation program is developed and competitions are held between computers or between a computer and a human being. It is confirmed that the algorithm and the position evaluation method can be effectively applied to the game model.