tsp问题俗称旅行商问题，一个商人从一个城市出发，经过所有的城市一次且仅一次回到出发的城市，问旅行商应当如何选择路径使总路径最短。本程序是用lingo软件编写的，只需要更改城市的数目以及距离矩阵即可。-tsp problem commonly known as the traveling salesman problem, a businessman from a city of departure, after all of the city once and only once return