#为什么有的人喜欢看烧脑剧？###什么是“烧脑”通常指影视作品悬念高深莫测，需要极高智商才能看通透，并且可以获得脑细胞燃烧的快感。###烧脑剧有什么？烧脑剧常常伴有大量专业知识，环环相扣的逻辑推理。看烧脑剧锻炼逻辑思维能力，从对话中提取出最重要的事物，并且把一些看起来没有多大关联的细枝末节推断出...

同步与异步同步：等待结果异步：不等待结果注意，异步常常伴随回调一起出现，但是异步不是回调，回调也不一定是异步如下代码就是同步,只要fn内部的循环完毕才能执行下面的代码functionfn(){for(vari=0;i<5000000000;i++){}}varstartTime=newDate().getTime...

[外链图片转存失败(img-cn4fbVDq-1563575047348)(https://upload-images.jianshu.io/upload_images/11158618-8c6f3d2b8ff0bec3.png?imageMogr2/auto-orient/strip|imageView2/2/w/1...

[外链图片转存失败(img-G32u6UQ8-1563572536495)(https://upload-images.jianshu.io/upload_images/11158618-a03a58b9b5ed5fc8.png?imageMogr2/auto-orient/strip|imageView2/2/w/1...

[外链图片转存失败(img-b0GOhxRY-1563571645197)(https://upload-images.jianshu.io/upload_images/11158618-ba249b916a32ba91.png?imageMogr2/auto-orient/strip|imageView2/2/w/1...

[外链图片转存失败(img-0GQ8QDNb-1563568792102)(https://upload-images.jianshu.io/upload_images/11158618-5bc7a2a4da359f48.png?imageMogr2/auto-orient/strip|imageView2/2/w/1...

[外链图片转存失败(img-yfi1VPyy-1563434266398)(https://upload-images.jianshu.io/upload_images/11158618-fc8784aa1868fbb5.png?imageMogr2/auto-orient/strip|imageView2/2/w/1...

[外链图片转存失败(img-zk4xNuy1-1563431241992)(https://upload-images.jianshu.io/upload_images/11158618-4e9cac1478aa949a.png?imageMogr2/auto-orient/strip|imageView2/2/w/1...

[外链图片转存失败(img-rmJXMGFs-1563388353181)(https://upload-images.jianshu.io/upload_images/11158618-dd813ed6e7f957c9.png?imageMogr2/auto-orient/strip|imageView2/2/w/1...