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题目背景 这是一道模板题 可以使用bitset，CDQ分治，K-DTree等方式解决。 题目描述 有 nn 个元素，第 ii 个元素有 a_iai、b_ibi、c_ici 三个属性，设 f(i)f(i) 表示满足 a_j \leq a_iaj≤ai 且 b_j \leq b_ibj≤bi 阅读全文
摘要：
On a grid map there are n little men and n houses. In each unit time, every little man can move one unit step, either horizontally, or vertically, to 阅读全文
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Cows are such finicky eaters. Each cow has a preference for certain foods and drinks, and she will consume no others. Farmer John has cooked fabulous 阅读全文