Open nijisakai opened 4 years ago
http://actionbook.bnu.edu.cn/ai_course/zh-hans/content/chapter1/%E7%AC%AC3%E8%8A%82%20%E8%AE%A9%E7%85%A7%E7%89%87%E5%8A%A8%E8%B5%B7%E6%9D%A5%E2%80%94%E7%94%9F%E6%88%90%E5%AF%B9%E6%8A%97%E7%BD%91%E7%BB%9C.html
http://actionbook.bnu.edu.cn/ai_course/zh-hans/content/chapter1/%E7%AC%AC3%E8%8A%82%20%E8%AE%A9%E7%85%A7%E7%89%87%E5%8A%A8%E8%B5%B7%E6%9D%A5%E2%80%94%E7%94%9F%E6%88%90%E5%AF%B9%E6%8A%97%E7%BD%91%E7%BB%9C.html