随笔分类 - 数据结构与算法
摘要:关于二叉树的遍历在面试时是企业经常容易考到的题目,这里做一下总结。 各类二叉树遍历的概念 二叉树有前序遍历,中序遍历和后序遍历三种。关于这三种遍历,网上资料有很多,在此就不做详细介绍了。主要需要记住顺序: 前序遍历 - 根->左->右 中序遍历 - 左->根->右 后序遍历 - 左->右->根 递归
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摘要:题目: Given an integer array nums, return the number of range sums that lie in [lower, upper] inclusive. Range sum S(i, j) is defined as the sum of the
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摘要:题目: Given a string s1, we may represent it as a binary tree by partitioning it to two non-empty substrings recursively. Below is one possible represen
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摘要:题目: Given n non-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the
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摘要:近日参加了一家国内某知名互联网公司的在线笔试,有一道算法题比较有意思,拿出来分享一下。 题目: 给定一个字符串,可以随意删除字符串里的任何字符(也可以不删除),目标是删除一些字符后让剩下的字符能够组成回文,并返回该输入字符串所能构成的最长回文长度。 例如,输入:"eabbfa"。 删除e和f后,构成
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摘要:题目: Given an array of integers, find out whether there are two distinct indices i and j in the array such that the difference between nums[i] and nums
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摘要:题目: Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains
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摘要:题目: A message containing letters from A-Z is being encoded to numbers using the following mapping: 'A' -> 1 'B' -> 2 ... 'Z' -> 26 Given an encoded me
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摘要:题目: Find the contiguous subarray within an array (containing at least one number) which has the largest product. For example, given the array [2,3,-2,
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摘要:题目: Given a list of airline tickets represented by pairs of departure and arrival airports [from, to], reconstruct the itinerary in order. All of the
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摘要:All DNA is composed of a series of nucleotides abbreviated as A, C, G, and T, for example: "ACGAATTCCG". When studying DNA, it is sometimes useful to
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摘要:The set [1,2,3,…,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order, We get the following sequenc
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摘要:Additive number is a string whose digits can form additive sequence. A valid additive sequence should contain at least three numbers. Except for the f
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摘要:Given an array of strings, group anagrams together. For example, given: ["eat", "tea", "tan", "ate", "nat", "bat"], Return: Note: 这道题要把所有字母组成相同的单词归为一类
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摘要:Given an integer n, count the total number of digit 1 appearing in all non-negative integers less than or equal to n. For example: Given n = 13, Retur
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摘要:题目: Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. Follow up: Did you use extra space? A straight forwa
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摘要:题目: Given an Iterator class interface with methods: next() and hasNext(), design and implement a PeekingIterator that support the peek() operation --
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摘要:Given a string of numbers and operators, return all possible results from computing all the different possible ways to group numbers and operators. Th
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摘要:题目: According to the Wikipedia's article: "The Game of Life, also known simply as Life, is a cellular automaton devised by the British mathematician J
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摘要:题目: The gray code is a binary numeral system where two successive values differ in only one bit. Given a non-negative integer n representing the total
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