摘要：
Given an unsorted array of integers, find the length of the longest consecutive elements sequence. 阅读全文
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Given two words (start and end), and a dictionary, find all shortest transformation sequence(s) from start to end 阅读全文
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Given two words (start and end), and a dictionary, find the length of shortest transformation sequence from start to end, such that: 阅读全文
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Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. 阅读全文
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ay you have an array for which the ith element is the price of a given stock on day i.
Design an algorithm to find the maximum profit. You may complete at most two transactions. 阅读全文
摘要：
Say you have an array for which the ith element is the price of a given stock on day i. 阅读全文
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ay you have an array for which the ith element is the price of a given stock on day i. 阅读全文
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Given a binary tree, find the maximum path sum. 阅读全文
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Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below. 阅读全文
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Follow up for problem "Populating Next Right Pointers in Each Node".
What if the given tree could be any binary tree? Would your previous solution still work? 阅读全文