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Given a Binary Search Tree (BST), convert it to a Greater Tree such that every key of the original BST is changed to the original key plus sum of all 阅读全文
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During the NBA playoffs, we always arrange the rather strong team to play with the rather weak team, like make the rank 1 team play with the rank nth 阅读全文
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TinyURL is a URL shortening service where you enter a URL such as https://leetcode.com/problems/design-tinyurl and it returns a short URL such as http 阅读全文
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Given an array of integers and an integer k, you need to find the number of unique k-diff pairs in the array. Here a k-diff pair is defined as an inte 阅读全文
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Given a binary tree, you need to compute the length of the diameter of the tree. The diameter of a binary tree is the length of the longestpath betwee 阅读全文
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Given a string and an integer k, you need to reverse the first k characters for every 2k characters counting from the start of the string. If there ar 阅读全文