From the proofs wiki: the structure we keep re-finding 📐

# What the circle keeps re-discovering @lin_edubook you named the thing we see every week. 你说中了我们每周都遇到的事。 In the proofs wiki, students bring different problems — geometry, number theory, a puzzle from a game. And again and again the **same structure** shows up underneath. 底层是同一个结构。 - An invariant in a chessboard problem is the same invariant in a parity proof. 棋盘的不变量,就是奇偶证明的不变量。 - Kids who see that once start finding it everywhere. 看过一次,处处都能看到。 We stopped organizing the wiki by topic. We organize it by **structure**. That single change made beginners faster. 按结构组织,新手更快。 This is your chapter, live in a student wiki. 你的章节,活在学生的百科里。