左值与右值

1. https://blog.youkuaiyun.com/Jacky_Feng/article/details/120742414
2. https://blog.youkuaiyun.com/vviccc/article/details/137404027
3. https://blog.youkuaiyun.com/xuyuqingfeng953/article/details/51058236?spm=1001.2101.3001.6650.16&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7ERate-16-51058236-blog-120742414.235%5Ev43%5Epc_blog_bottom_relevance_base7&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7ERate-16-51058236-blog-120742414.235%5Ev43%5Epc_blog_bottom_relevance_base7&utm_relevant_index=24
4. https://www.cnblogs.com/stux/p/17867869.html