minimum time to activate string core interview pattern 模式
1 道题目
模式页适合用来建立可复用解题框架。先识别题目特征，再按固定流程解释状态定义、转移和边界。
识别信号
- The candidate demonstrates understanding of binary search and efficient substring counting.
- Look for an explanation of how to manage the time complexity when dealing with large values of `n` and `k`.
解题流程
- 1. 明确窗口/状态定义
- 2. 更新状态并维护约束
- 3. 用边界样例验证
常见失分点
- Overlooking the fact that not all `t` values will result in valid substrings; carefully managing how many valid substrings are generated is crucial.