一个喝醉的酒鬼在街道上游走。整个城市街道呈网格状分布,酒鬼每走到一个十字路口,都会概率均等地选择一条路(包括自己来时的那条路)继续走下去。他最终能够回到出发点的概率是多少呢?答案是100%!刚开始,这个醉鬼可能会越走越远,但最后他总能找到回家的路。假设有一条水平直线,从某个 A drunk alcoholic wandered the streets. The streets of the entire city are in a grid-like pattern. Every time a drunk walks to a crossroad, he or she will continue to walk with the same probability of choosing a road (including the road from which he came). What is the probability that he will eventually be able to get back to the starting point? The answer is 100%! At first, the drunkard may go further and further, but in the end he will always find his way home. Suppose you have a horizontal line from one