求解TSP问题的Hopfield网络设计。在一个城市集合{A,B,C,D}中找出一个最短且经过每个城市各一次并且回到起点的路径。-TSP problem Hopfield network design. In a city the set {A, B, C, D} in finding a shortest and after each city once and returned to the starting point of each route.