07 2021 档案

摘要:直接看代码: public class Demo { public static void main(String[] args) { String s1 = "hello"; String s2 = s1.substring(0,2); System.out.println(s1==s2);//f 阅读全文
posted @ 2021-07-27 10:07 fridays 阅读(287) 评论(0) 推荐(0)
摘要:![](https://img2020.cnblogs.com/blog/2090278/202108/2090278-20210803142912385-1709007308.jpg) 阅读全文
posted @ 2021-07-12 10:52 fridays 阅读(65) 评论(0) 推荐(0)