This first issue of 2021 contains two scientific articles. The first one An Efficient AI-based Method to Play the Mahjong Game with the Knowledge and Game-tree Searching Strategy by Mingyan Wang et al. deals with the imperfect information game of Mahjong which has a huge average size of information sets. In order to approach this popular, complex and challenging game, the authors propose to use opponent models, knowledge and tree search.

中文翻译：

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社论：麻将、数独和国际象棋

2021 年第一期包含两篇科学文章。王明彦等人的第一个基于 AI 的高效麻将游戏方法与知识和博弈树搜索策略。处理具有巨大平均信息集大小的不完全信息麻将游戏。为了应对这种流行、复杂和具有挑战性的游戏，作者建议使用对手模型、知识和树搜索。