从前序与中序遍历序列构造二叉树。题意是给一个二叉树的前序遍历和中序遍历，请根据这两个遍历，把树构造出来。例子， For example, given preorder = [3,9,20,15,7] inorder = [9,3,15,20,7] Return the following binar ...
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其他好文 时间：
2020-04-21 13:31:31
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65
Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binary tree [3 ...
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其他好文 时间：
2020-04-21 09:51:36
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66
Problem : A matrix is Toeplitz if every diagonal from top left to bottom right has the same element. Now given an M x N matrix, return True if and onl ...
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2020-04-20 12:00:41
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54
Cutting an integer means to cut a K digits lone integer Z into two integers of (K/2) digits long integers A and B. For example, after cutting Z = 1673 ...
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其他好文 时间：
2020-04-20 11:55:53
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62
Problem : Given two integers L and R, find the count of numbers in the range [L, R] (inclusive) having a prime number of set bits in their binary repr ...
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其他好文 时间：
2020-04-20 11:50:44
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65
Given n integers, your task is to pick k out of them so that the picked number are minimum when do bitwise “AND” among all of them. For example, there ...
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其他好文 时间：
2020-04-20 11:39:23
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56
A vertex cover of a graph is a set of vertices such that each edge of the graph is incident to at least one vertex of the set. Now given a graph with ...
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其他好文 时间：
2020-04-20 01:33:53
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85
Problem : Given a sorted array, two integers k and x, find the k closest elements to x in the array. The result should also be sorted in ascending ord ...
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其他好文 时间：
2020-04-19 00:38:45
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62
Problem : Given a positive integer, check whether it has alternating bits: namely, if two adjacent bits will always have different values. Example 1: ...
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其他好文 时间：
2020-04-18 22:43:40
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74
Problem : Given a non empty array of non negative integers nums, the degree of this array is defined as the maximum frequency of any one of its elemen ...
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其他好文 时间：
2020-04-18 18:27:07
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49
