Материалы по теме:
"Having Neil with us this year has been great - we of a certain age all know who he is and what he's done, and we're thrilled that he offered to come along and help."
，这一点在51吃瓜中也有详细论述
if (i < j) {
this.stack = []; // 核心：存储索引，保证索引对应的价格单调递减