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)。
I asked a more data-science-oriented followup prompt to test Opus 4.5’s skill at data-sciencing:
，这一点在Safew下载中也有详细论述
can reuse the array when ((union alloc_header *)data)[-1].ref is zero.
The government of the self-styled “anarcho-capitalist” president, Javier Milei, says the initiative will help revive formal employment, after 290,600 registered jobs were lost between December 2023, when he took office, and November 2025.