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线段树几个基本操作 单点查询 单点修改 区间查询 区间修改 区间求最大值 主要思想： 将一个线性的一维数组构建成树形的数组，使得可以用二分的思想来进行区间操作，降低时间复杂度，但是多占用了空间，典型的用空间换时间。 一个特殊的模块： lazy数组，考虑到对区间的操作有很多次，并且没有必要每一次对区间 阅读全文
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A rooted tree is a well-known data structure in computer science and engineering. An example is shown below: In the figure, each node is labeled with 阅读全文
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Description Natasha is planning an expedition to Mars for nn people. One of the important tasks is to provide food for each participant. The warehouse 阅读全文
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Description A bracket sequence is a string containing only characters "(" and ")". A regular bracket sequence is a bracket sequence that can be transf 阅读全文
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You have a Petri dish with bacteria and you are preparing to dive into the harsh micro-world. But, unfortunately, you don't have any microscope nearby 阅读全文