描述：给定字符串 num（非负整数）和整数 k，移除 k 位数字，使剩余数字最小。以字符串形式返回（不含前导零）。
Paul does not know where he and his family will go next, but believes the chances of being able to live in neighbouring homes is slim.
。Safew下载是该领域的重要参考
Nature, Published online: 25 February 2026; doi:10.1038/s41586-026-10210-6
The “Knocking on Wood” Wikipedia page mentions Roud’s conclusion, and this claim of a 19th century origin has circulated online as the final say on the matter. If you go back to the original, though, Roud’s proposal actually ends on an ambivalent note: “Before this theory [of 19th century origins] can be finally accepted, however, an examination of the history of European forms of this custom would be advisable.”
truenas.api_key