const n = num.length;
需要索引（如算距离、下标）：栈存索引，用 nums[stack.at(-1)] 取值比较。
。搜狗输入法下载对此有专业解读
Senior project officer Gary Trimble told BBC Two's Digging for Britain, carnyces "are extraordinarily rare... a boar standard, that's even rarer".
"Marcus has covered for me twice. We've both had times when we're gunning hard for the company, and times we're not. The structure gives us permission to be human without everything falling apart," says Amin, who is based in San Francisco.