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Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction 阅读全文
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Given a binary tree, find its maximum depth.The maximum depth is the number of nodes along the longest path from the root node down to the farthest le 阅读全文
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You are climbing a stair case. It takes n steps to reach to the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can you cli 阅读全文
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Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum. Example: Foll 阅读全文
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Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists. Example: 阅读全文
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Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. An input string is valid if: No 阅读全文
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You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contai 阅读全文
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Given an array of integers, return indices of the two numbers such that they add up to a specific target.You may assume that each input would have exa 阅读全文