摘要: Given two strings a and b we define a*b to be their concatenation. For example, if a = "abc" and b = "def" then a*b = "abcdef". If we think of concate 阅读全文
posted @ 2018-05-10 16:54 cglong 阅读(251) 评论(0) 推荐(0) 编辑