2018 年 3月随笔档案 - Beserious

leetcode 105. Construct Binary Tree from Preorder and Inorder Traversal

摘要：Given preorder and inorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do not exist in the tree. 思路还是比较简单的，在中阅读全文

posted @ 2018-03-26 22:04 Beserious 阅读(108) 评论(0) 推荐(0)

leetcode 309. Best Time to Buy and Sell Stock with Cooldown

摘要：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

posted @ 2018-03-23 23:55 Beserious 阅读(151) 评论(0) 推荐(0)

leetcode 714. Best Time to Buy and Sell Stock with Transaction Fee

摘要：Your are given an array of integers prices, for which the i th element is the price of a given stock on day i; and a non negative integer fee represen 阅读全文

posted @ 2018-03-23 23:47 Beserious 阅读(255) 评论(0) 推荐(0)

leetcode 32. Longest Valid Parentheses

摘要：Given a string containing just the characters and , find the length of the longest valid (well formed) parentheses substring. For , the longest valid 阅读全文

posted @ 2018-03-21 21:24 Beserious 阅读(119) 评论(0) 推荐(0)

leetcode 224. Basic Calculator

摘要：Implement a basic calculator to evaluate a simple expression string. The expression string may contain open ( and closing parentheses ), the plus + or 阅读全文

posted @ 2018-03-21 21:06 Beserious 阅读(120) 评论(0) 推荐(0)

leetcode 540. Single Element in a Sorted Array

摘要：Given a sorted array consisting of only integers where every element appears twice except for one element which appears once. Find this single element 阅读全文

posted @ 2018-03-21 20:16 Beserious 阅读(134) 评论(0) 推荐(0)

leetcode 109. Convert Sorted List to Binary Search Tree

摘要：Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. For this problem, a height balanced bina 阅读全文

posted @ 2018-03-17 10:27 Beserious 阅读(129) 评论(0) 推荐(0)

leetcode 3. Longest Substring Without Repeating Characters

摘要：Given a string, find the length of the longest substring without repeating characters. 思路：用map维护区间内各个字母的数量，然后遇到已经访问过的就进行滑动区间，来得到符合条件的区间，然后求最大区间长度。虽然时阅读全文

posted @ 2018-03-17 10:21 Beserious 阅读(130) 评论(0) 推荐(0)

leetcode 84. Largest Rectangle in Histogram

摘要：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 hist 阅读全文

posted @ 2018-03-13 22:36 Beserious 阅读(149) 评论(0) 推荐(0)

leetcode 338. Counting Bits

摘要：Given a non negative integer number num. For every numbers i in the range 0 ≤ i ≤ num calculate the number of 1's in their binary representation and r 阅读全文

posted @ 2018-03-12 20:36 Beserious 阅读(177) 评论(0) 推荐(0)

leetcode 797. All Paths From Source to Target

摘要：Given a directed, acyclic graph of N nodes. Find all possible paths from node 0 to node N 1, and return them in any order. The graph is given as follo 阅读全文

posted @ 2018-03-11 20:36 Beserious 阅读(384) 评论(0) 推荐(0)

leetcode 796. Rotate String

摘要：We are given two strings, A and B. A shift on A consists of taking string A and moving the leftmost character to the rightmost position. For example, 阅读全文

posted @ 2018-03-11 20:20 Beserious 阅读(290) 评论(0) 推荐(0)

leetcode 153. Find Minimum in Rotated Sorted Array

摘要：Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). Find 阅读全文

posted @ 2018-03-10 21:32 Beserious 阅读(146) 评论(0) 推荐(0)

leeetcode 735. Asteroid Collision

摘要：We are given an array asteroids of integers representing asteroids in a row. For each asteroid, the absolute value represents its size, and the sign r 阅读全文

posted @ 2018-03-09 20:13 Beserious 阅读(180) 评论(0) 推荐(0)

leetcode 795. Number of Subarrays with Bounded Maximum

摘要：We are given an array A of positive integers, and two positive integers L and R (L R`的数字,那么此时就重新开始计数。思路很简单，但是实现起来..... 代码中b维护的是`& A, int L, int R) { i 阅读全文

posted @ 2018-03-08 18:57 Beserious 阅读(328) 评论(0) 推荐(0)

leetcode 792. Number of Matching Subsequences

摘要：Given string S and a dictionary of words words, find the number of words[i] that is a subsequence of S. 思路:先用vector记录每个字母出现的位置，然后遍历每个单词，如果每个字母的位置是递增的那阅读全文

posted @ 2018-03-06 21:58 Beserious 阅读(350) 评论(0) 推荐(0)

leetcode 4. Median of Two Sorted Arrays

摘要：There are two sorted arrays nums1 and nums2 of size m and n respectively. Find the median of the two sorted arrays. The overall run time complexity sh 阅读全文

posted @ 2018-03-01 21:30 Beserious 阅读(132) 评论(0) 推荐(0)

leetcode 334. Increasing Triplet Subsequence

摘要：Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array. Formally the function should: 阅读全文

posted @ 2018-03-01 11:20 Beserious 阅读(96) 评论(0) 推荐(0)

leetcode 235. Lowest Common Ancestor of a Binary Search Tree

摘要：Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. 还是bst树，bst树的左节点小于根节点小于右节点，依据此性质递归比较既可以找到公共父节点。注阅读全文

posted @ 2018-03-01 10:36 Beserious 阅读(86) 评论(0) 推荐(0)

leetcode 459. Repeated Substring Pattern

摘要：Given a non empty string check if it can be constructed by taking a substring of it and appending multiple copies of the substring together. You may a 阅读全文

posted @ 2018-03-01 10:32 Beserious 阅读(103) 评论(0) 推荐(0)

leetcode 501. Find Mode in Binary Search Tree

摘要：Given a binary search tree (BST) with duplicates, find all the mode(s) (the most frequently occurred element) in the given BST. Assume a BST is define 阅读全文

posted @ 2018-03-01 09:41 Beserious 阅读(110) 评论(0) 推荐(0)

leetcode 530. Minimum Absolute Difference in BST

摘要：Given a binary search tree with non negative values, find the minimum absolute difference between values of any two nodes. 题目大意，求bst树任意两点的最小绝对距离。思路，中阅读全文

posted @ 2018-03-01 09:34 Beserious 阅读(113) 评论(0) 推荐(0)

leetcode 543. Diameter of Binary Tree

摘要：Given a binary tree, you need to compute the length of the diameter of the tree. The diameter of a binary tree is the length of the longest path betwe 阅读全文

posted @ 2018-03-01 09:28 Beserious 阅读(102) 评论(0) 推荐(0)

leetcode 551. Student Attendance Record I

摘要：You are given a string representing an attendance record for a student. The record only contains the following three characters: 'A' : Absent. 'L' : L 阅读全文

posted @ 2018-03-01 09:14 Beserious 阅读(121) 评论(0) 推荐(0)

leetcode 563. Binary Tree Tilt

摘要：Given a binary tree, return the tilt of the whole tree. The tilt of a tree node is defined as the absolute difference between the sum of all left subt 阅读全文

posted @ 2018-03-01 09:12 Beserious 阅读(106) 评论(0) 推荐(0)

leetcode 598. Range Addition II

摘要：Given an m n matrix M initialized with all 0's and several update operations. Operations are represented by a 2D array, and each operation is represen 阅读全文

posted @ 2018-03-01 09:09 Beserious 阅读(106) 评论(0) 推荐(0)

leetcode 599. Minimum Index Sum of Two Lists

摘要：Suppose Andy and Doris want to choose a restaurant for dinner, and they both have a list of favorite restaurants represented by strings. You need to h 阅读全文

posted @ 2018-03-01 09:05 Beserious 阅读(106) 评论(0) 推荐(0)

leetcode 606. Construct String from Binary Tree

摘要：You need to construct a string consists of parenthesis and integers from a binary tree with the preorder traversing way. The null node needs to be rep 阅读全文

posted @ 2018-03-01 08:59 Beserious 阅读(107) 评论(0) 推荐(0)

leetcode 690. Employee Importance

摘要：You are given a data structure of employee information, which includes the employee's unique id, his importance value and his direct subordinates' id. 阅读全文

posted @ 2018-03-01 08:53 Beserious 阅读(117) 评论(0) 推荐(0)