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Find the sum of all left leaves in a given binary tree. Example: 3 / \ 9 20 / \ 15 7 There are two left leaves in the binary tree, with values 9 and 1 阅读全文
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Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number. The function 阅读全文
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Given a Binary Search Tree and a target number, return true if there exist two elements in the BST such that their sum is equal to the given target. E 阅读全文
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Say 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 comple 阅读全文
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Assume you are an awesome parent and want to give your children some cookies. But, you should give each child at most one cookie. Each child i has a g 阅读全文
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Given an arbitrary ransom note string and another string containing letters from all the magazines, write a function that will return true if the rans 阅读全文