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Description: You have a total of n coins that you want to form in a staircase shape, where every k-th row must have exactly k coins. Given n, find the 阅读全文
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Description: Given scores of N athletes, find their relative ranks and the people with the top three highest scores, who will be awarded medals: "Gold 阅读全文
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Description: Given a string S, return the "reversed" string where all characters that are not a letter stay in the same place, and all letters reverse 阅读全文
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Description: Given the root node of a binary search tree (BST) and a value. You need to find the node in the BST that the node's value equals the give 阅读全文
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Description: Given a non-negative integer c, your task is to decide whether there're two integers a and b such that a2 + b2 = c. Example 1: Input: 5 O 阅读全文
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Description: A boomerang is a set of 3 points that are all distinct and not in a straight line. Given a list of three points in the plane, return whet 阅读全文