区间·cancellation·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
- Look for correct handling of repeated execution and cancellation at the right moment.
- Watch for the proper use of `setInterval` for periodic execution and `setTimeout` for cancellation.
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
- Failing to clear the interval properly can cause the function to continue executing beyond the cancellation time.