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Problem Description Given a tree (a connected graph with no cycles), you have to find the farthest nodes in the tree. The edges... 阅读全文
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【定义】 给定一棵树，树中的每条边都有一个权值。 树中两点的距离：连接两点的路径边权之和树的直径：树中最远的两个节点之间的距离树的最长链：连接树中最远的两个结点的路径【实现】 树的直径通常有两种求法，时间复杂度均为O(n)。 假设树以 n 个点 n-1 条边的... 阅读全文
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Problem Description Nura wants to buy k gadgets. She has only s burles for that. She can buy each gadget for dollars or for pou... 阅读全文
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Problem Description Lavrenty, a baker, is going to make several buns with stuffings and sell them. Lavrenty has n grams of dou... 阅读全文
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Problem Description 小度熊拿到了一个无序的数组，对于这个数组，小度熊想知道是否能找到一个k 的区间，里面的 k 个数字排完序后是连续的。 现在小度熊增加题目难度，他不想知道是否有这样的 k 的区间，而是想知道有几个这样的 k 的区间... 阅读全文
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Problem Description There is a tree(the tree is a connected graph which contains n points and n−1 edges),the points are labeled... 阅读全文
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Problem Description 度度熊是一只喜欢探险的熊，一次偶然落进了一个m*n矩阵的迷宫，该迷宫只能从矩阵左上角第一个方格开始走，只有走到右上角的第一个格子才算走出迷宫，每一次只能走一格，且只能向上向下向右走以前没有走过的格子，每一个格子中都... 阅读全文
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Problem Description A list of n integers are given. For an integer x you can do the following operations: + let the binary rep... 阅读全文
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Problem Description According to the Automobile Collision Monitor (ACM), most fatal traffic accidents occur on two-way streets.... 阅读全文
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Problem Description The Genographic Project is a research partnership between IBM and The National Geographic Society that is a... 阅读全文