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Given a range [m, n] where 0 <= m <= n <= 2147483647, return the bitwise AND of all numbers in this range, inclusive. For example, given the range [5, 阅读全文
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Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example:Given the below binary tree and sum 阅读全文
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Additive number is a string whose digits can form additive sequence. A valid additive sequence should contain at least three numbers. Except for the f 阅读全文
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Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of LCA on Wikipedia 阅读全文
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Given a roman numeral, convert it to an integer. Input is guaranteed to be within the range from 1 to 3999. 基本字符 I V X L C D M 相应的阿拉伯数字表示为 1 5 10 50 1 阅读全文
摘要：
Given an integer, convert it to a roman numeral. Input is guaranteed to be within the range from 1 to 3999. 基本字符 I V X L C D M 相应的阿拉伯数字表示为 1 5 10 50 1 阅读全文