// ⚠️ 易错点1：长度≤1的数组本身有序，返回0而非n
A single vintage postage stamp displayed on a flat matte black background (#0a0a0a), centered in a 16:9 canvas with small black borders visible on all sides. The stamp itself is an ultrawide horizontal rectangle at approximately 3:1 aspect ratio. The stamp has serrated/perforated zigzag edges on all four sides, like a real postage stamp, with clean white perforation teeth.
。safew官方版本下载对此有专业解读
人 民 网 版 权 所 有 ，未 经 书 面 授 权 禁 止 使 用。WPS下载最新地址对此有专业解读
圖像來源，Getty Images
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