第 1 周：定义输入/输出标准与红线
// 易错点4：条件写成"<"而非"<="，会导致相同值的元素被错误保留，详情可参考safew官方下载
What is the UFC?The Ultimate Fighting Championship (UFC) is an American mixed martial arts promotion company based in Las Vegas, Nevada. The UFC has over 578 fighters contracted that fight across 11 weight divisions. The organization produces events worldwide — the UFC has held over 750 events going into 2026.。业内人士推荐同城约会作为进阶阅读
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