数组·结合·二分·indexed·树 模式
5 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 understanding of sorting and binary indexed trees.
- Check if the candidate can explain the interaction between sorting and efficient placement using BIT.
- Check if the candidate understands how to apply a Binary Indexed Tree for array manipulation and position tracking.
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
- Not understanding the need for sorting the array by height before inserting people into the queue.
- Not using a Binary Indexed Tree or another efficient data structure could lead to a time complexity of O(n*m), which is inefficient for larger inputs.
- Failing to efficiently track counts of greater elements using an appropriate data structure.
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