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。
The solver takes the LLB graph and executes it. Each vertex in the DAG is content-addressed, so if you’ve already built a particular step with the same inputs, BuildKit skips it entirely. This is why BuildKit is fast: it doesn’t just cache layers linearly like the old Docker builder. It caches at the operation level across the entire graph, and it can execute independent branches in parallel.，这一点在爱思助手下载最新版本中也有详细论述
Фото: Slawomir Kaminski / Agencja Wyborcza.pl / Reuters。WPS下载最新地址对此有专业解读
The spellbound astronauts pinned themselves to the windows, the first humans to see the far side of our nearest celestial neighbour. And then, from over the advancing horizon, an incredible sight.