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Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element. For exam 阅读全文
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Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm s 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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题目：给几个Email的list，输出全部list的交集（在全部list中都出现过的email）。 思路：用set记录前i个list中都含有的email，当进行第i+1时，检查每个email是否在该set中存在，若存在，则说明该email在前i+1个list中都有，则将它记录到另一个set中。整个算 阅读全文
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Divide two integers without using multiplication, division and mod operator. If it is overflow, return MAX_INT. 思路： 采用位运算。我们先将两个数都看作是正数。 我们将除数左移一位就是将它 阅读全文
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问题：给一个循环链表，和一个要删除的节点，将其删除。时间复杂度O(n)。核心代码如下： 1 ListNode *next = node->next; 2 ListNode *cur = node; 3 while (cur->next != node) 4 cur = cur->next; 5 cu 阅读全文
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Compare two version numbers version1 and version2.If version1 > version2 return 1, if version1 < version2 return -1, otherwise return 0. You may assum 阅读全文
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给一个sorted array 0 0 0 1 1 1 1，然后找出第一个1的位置。 边界情况：array为空或者全0。 思路：二分查找。为了优化，可以先判断最后一个数是不是0。 1 class Solution 2 { 3 public: 4 int FindBrokenCode(vector<i 阅读全文
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Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining. 阅读全文
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The count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ... 1 is read off as "one 1" or 11.11 is read off 阅读全文