题解 | #汉诺塔问题#

#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param n int整型 
# @return string字符串一维数组
#

class Solution:
    
    def a_to_b(self, n, a_str, b_str):
        stage_log = []
        if n == 1:
            stage_log.append("move from {} to {}".format(a_str, b_str))
        else:
            all_direct = set(["left", "mid", "right"])
            another_elem = list(all_direct-set([a_str, b_str]))[0]
            stage_log.extend(self.a_to_b(n-1, a_str, another_elem))
            stage_log.append("move from {} to {}".format(a_str, b_str))
            stage_log.extend(self.a_to_b(n-1, another_elem, b_str))
        return stage_log

    def getSolution(self, n):
        stage_log =  self.a_to_b(n, "left", "right")
        return stage_log