第五条 纳税人开具增值税专用发票，应当分别列明销售额和增值税税额。
// 当前索引入栈，作为左侧天数的候选（易错点4：存索引而非温度值）
，更多细节参见safew官方版本下载
Systematic scaling, found phase transition at d=16
栈（stack）是先进后出的数据结构。单调栈在入栈时通过一定规则保持栈内元素有序（单调递增或单调递减），从而把「找左侧/右侧第一个更大/更小元素」从 O(n²) 降到 O(n)。
There are two colorways for both the phone and the ecosystem of accessories. There's a silver-aluminum edition and a nifty-looking grey version. This doesn't matter to actual consumers because, well, it's just a concept design. It does look like the company's magnetic attachment technology could make it to some actual products down the line.