文中符号：\(\operatorname{Period}(s)\)：字符串\(s\)的周期集合。\(\operatorname{Per}(s)\)：字符串\(s\)的最小周期。循环节：\(x\in\operatorname{Period}(s)\)且\(x|\operatorname{len}(S)\)。\(\operatorname{Cyc}(s)\)：\(s\)的最小循环节。\(\operatorname{endpos}(