Game theory + bitwise enumeration — enumerate how many global halving operations are performed to compute the minimum step count.

博弈 + 位运算枚举，通过枚举全体除二的次数来计算最少步数。

Persistent segment tree + segment tree for range AND set-size queries with forced online mode.

主席树 + 线段树维护区间与操作，处理强制在线的区间子集大小查询。

Working through the canonical suffix-array problems from Luo Suiqian's 2009 IOI national team paper, using the SAIS template.

基于罗穗骞2009年国集论文，使用SAIS模板，整理后缀数组经典题型与解题套路。

Lucas numbers + Union-Find, solving a cycle-cover counting problem.

卢卡斯数列 + 并查集，处理环上覆盖计数问题。