二分查找 二分答案 笔记

https://cdn.all-dream.com/user%2F1e3abe408f644377bc8c86a452d6e1a9%2F20190705_070402_zoom_0.mp4

https://cdn.all-dream.com/user%2F1e3abe408f644377bc8c86a452d6e1a9%2F20190701_183621_05.mp4