说明：  看代码之前，请先弄明白pso是怎么回事。然后请对应着来：程序中用Agent代表一只鸟，PSO代表鸟群。阅读源代码，不要顺着看，先看main(),然后按照出现的东西的顺序，一个一个得来，呵呵，纯粹是建议。
(Before looking at the code, you figure out how it pso. Then please correspond to: Program Agent on behalf of a bird, PSO representative of the flock. Read the source code, do not look down, look main (), and then follow the order of appearance of things, one by one, come, Oh, purely recommendations.)