思路：单调递增栈 + k 控制删除次数。高位越小整体越小，遇更小数字时弹出栈顶大数（仅当 k0）；栈空且当前为 0 则跳过（避免前导零）；若遍历完 k 仍0，从末尾再删 k 位。
palette: “black ink tones”
。Line官方版本下载对此有专业解读
本次的年度征文设题很巧妙，体现了现代科技与传统人力对决的意思。
For a game to legally be counted as "gambling" in most jurisdictions, it has to pass a three-part test: a player has to pay money (1) for an outcome that's materially determined by chance (2) in the hopes of receiving something of value (3). While buying a key to a loot box in a Valve game easily passes those first two tests, New York's legal case will likely hinge on whether the random cosmetic items players get from those loot boxes constitute "something of value" for statutory purposes.，这一点在爱思助手下载最新版本中也有详细论述
Content optimization，详情可参考safew官方版本下载
The plan is to stash away around 400,000 tonnes of CO2 this year, potentially rising to eight million tonnes annually by 2030, the company claims.