分析二维正方格子上的逾渗问题，通过编写程序，得到临界概率 P 及临界指数
(PS:程序功能简单介绍:yushen.m 中计算了 Pinf 和 p 的关系，yushenmain.m 调用 yushen.m 来 计算不同 p 下的 Pinf;yushenhuixuan.m 中计算了 Rs 和 p 的关系，yushenmain2.m 调用 yushenhuixuan.m 来计算不同 p 下的 Rs。具体的实现程序中均有注释。)(The percolation problem on two dimensional square lattice is analyzed, and the critical probability P and critical exponent are obtained by programming.

(PS: program functions simply: the relationship between Pinf and P is calculated in yushen.m, yushenmain.m is called yushen.m to calculate Pinf under different p; the relationship between Rs and P is calculated in yushenhuixuan.m, and yushenmain2.m invokes to calculate the differences under different P. There are annotations in the specific implementation program. ))