POFEI_IS_SHIT-优快云博客

原创 30天自制操作系统-第6,7,8天

内容可以看看书，程序就是替换下asmhead.nas，生成的haribote.sys写入u盘的数据起始区域。https://github.com/PofeiShit/os第6天分割编译与中断处理第7天 FIFO与鼠标控制按下‘A’之后第八天鼠标控制与32位模式切换...

2018-09-02 16:04:20 585 1

原创 30天自制操作系统-显示鼠标指针

0.准备克服了之前读取u盘和导入c语言的困难，接下来就是一些c语言和图形界面的编程，只要将作者提供的文件夹里的asmhead.nas更改，然后make img生成的haribote.sys写入u盘，ipl10.bin无须更改，写入u盘就可以1.结果 ...

2018-08-26 10:53:53 539

原创 30天自制操作系统-导入c语言

0.准备换了一个32G的u盘，不过没关系按照之前的博客30天自制操作系统-Hello OS填写fat32文件格式。对于每一个u盘，要注意逻辑扇区和具体物理扇区的关系：选定59904扇区作为写入磁盘数据的起始，对应的柱面和磁头和扇区写入ipl10.nas然后要更改asmhead.nas。该文件的作用将从保护模式跳至实模式，具体的可以看该博客《30天自制操作系统》学习...

2018-08-19 18:21:06 788 1

原创 30天自制操作系统-Hello OS

0.准备代码使用的书本中的，使用8G的fat32格式u盘，不过对于Hello OS程序来言，开头的文件格式不需要也可以，只不过调用bios的输出字符函数（int 0x10)。并未读取u盘内的数据。 fat32文件格式的书写，可以使用winhex工具，先点击工具->打开磁盘->选择你的u盘。然后再查看->模板管理器->选择Boot Sector FAT32->应...

2018-08-19 17:37:50 4649 1

原创 30天自制操作系统-startHaribote

0.准备书中这里将显示代码分到Haribote.nas。org 0xc400载入内存中。对于每一个nasm生成的bin文件而言都是从0x0000000开始的，也就是说我们可以把bin文件载入到u盘的任意扇区，从上一个博客我们将30697的扇区载入到内存地址为0x8200中，所以我们把haribote.bin文件放到u盘的30698扇区，内存地址从0x8400开始，所以首先将haribote...

2018-08-12 16:52:50 801 2

原创 30天自制操作系统-读取u盘数据

0.准备再读取u盘这一节中，花费了一个月时间才成功，看到网站上有些博主说使用fat12文件格式的u盘，然后改下读取u盘的chs就能成功，有些博主说要用fat32文件格式的，再改chs也可以。我试了很久都不成功，实践证明还是要原理掌握了，才能实验成功。先说下fat12文件格式的程序中的地址为什么是0xc200，0x4200+0x8000,0x8000是我们指定的内存读取地址，那么0x4200...

2018-08-12 16:27:02 1944

A sequence of numbers is called a wiggle sequence if the differences between successive numbers strictly alternate between positive and negative. The first difference (if one exists) may be either pos...

2018-07-06 22:35:58 139

原创 322. Coin Change

You are given coins of different denominations and a total amount of money amount. Write a function to compute the fewest number of coins that you need to make up that amount. If that amount of money ...

2018-06-28 20:16:02 285

原创 213. House Robber II

You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed. All houses at this place are arranged in a circle. That means the first house is ...

2018-06-22 19:20:01 136

原创 154. Find Minimum in Rotated Sorted Array II

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 the minimum element.The array may contain dupl...

2018-06-18 13:03:40 157

原创 153. Find Minimum in Rotated Sorted Array

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 the minimum element.You may assume no duplicat...

2018-06-18 12:50:12 293

原创 81. Search in Rotated Sorted Array II

Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand.(i.e., [0,0,1,2,2,5,6] might become [2,5,6,0,0,1,2]).You are given a target value to search. If found in t...

2018-06-17 14:16:09 137

原创 48. Rotate Image

You are given an n x n 2D matrix representing an image.Rotate the image by 90 degrees (clockwise).Note:You have to rotate the image in-place, which means you have to modify the input 2D matrix directl...

2018-06-12 21:31:32 128

原创 560. Subarray Sum Equals K

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k.Example 1:Input:nums = [1,1,1], k = 2Output: 2Note:The length of the arra...

2018-06-10 22:27:23 192

原创 377. Combination Sum IV

Given an integer array with all positive numbers and no duplicates, find the number of possible combinations that add up to a positive integer target.Example:nums = [1, 2, 3]target = 4The possible...

2018-06-07 21:34:09 173

原创 673. Number of Longest Increasing Subsequence

Given an unsorted array of integers, find the number of longest increasing subsequence.Example 1:Input: [1,3,5,4,7]Output: 2Explanation: The two longest increasing subsequence are [1, 3, 4, 7] and [...

2018-06-06 21:26:22 155

原创 410. Split Array Largest Sum

Given an array which consists of non-negative integers and an integer m, you can split the array into m non-empty continuous subarrays. Write an algorithm to minimize the largest sum among these m sub...

2018-06-06 21:12:41 155

转载 813. Largest Sum of Averages

We partition a row of numbers A into at most K adjacent (non-empty) groups, then our score is the sum of the average of each group. What is the largest score we can achieve?Note that our partition mus...

2018-06-04 20:49:01 233

原创 392. Is Subsequence

Given a string s and a string t, check if s is subsequence of t.You may assume that there is only lower case English letters in both s and t. t is potentially a very long (length ~= 500,000) string, a...

2018-05-23 20:49:12 143

原创 368. Largest Divisible Subset

Given a set of distinct positive integers, find the largest subset such that every pair (Si, Sj) of elements in this subset satisfies: Si % Sj = 0 or Sj % Si = 0.If there are multiple solutions, retur...

2018-05-22 19:53:06 158

原创 494. Target Sum

You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its new symbol.Find out how man...

2018-05-19 16:22:15 175

原创 214. Shortest Palindrome

Given a string s, you are allowed to convert it to a palindrome by adding characters in front of it. Find and return the shortest palindrome you can find by performing this transformation.Example 1:In...

2018-05-11 20:50:52 285

原创 516. Longest Palindromic Subsequence

Given a string s, find the longest palindromic subsequence's length in s. You may assume that the maximum length of s is 1000.Example 1:Input: "bbbab"Output: 4One possible longest palindromic subseq...

2018-05-10 21:48:59 215

原创 647. Palindromic Substrings

Given a string, your task is to count how many palindromic substrings in this string.The substrings with different start indexes or end indexes are counted as different substrings even they consist of

2018-05-09 21:12:24 92

原创 581. Shortest Unsorted Continuous Subarray

Given an integer array, you need to find one continuous subarray that if you only sort this subarray in ascending order, then the whole array will be sorted in ascending order, too.You need to find the

2018-05-08 21:46:48 203

原创 718. Maximum Length of Repeated Subarray

Given two integer arrays A and B, return the maximum length of an subarray that appears in both arrays.Example 1:Input:A: [1,2,3,2,1]B: [3,2,1,4,7]Output: 3Explanation: The repeated subarray with

2018-05-05 11:26:42 116

原创 665. Non-decreasing Array

Given an array with n integers, your task is to check if it could become non-decreasing by modifying at most 1 element.We define an array is non-decreasing if array[i] <= array[i + 1] holds for every i

2018-05-03 21:48:35 97

原创 643. Maximum Average Subarray I

Given an array consisting of n integers, find the contiguous subarray of given length k that has the maximum average value. And you need to output the maximum average value.Example 1:Input: [1,12,-5,-6

2018-05-03 21:10:48 116

原创 746. Min Cost Climbing Stairs

On a staircase, the i-th step has some non-negative cost cost[i] assigned (0 indexed).Once you pay the cost, you can either climb one or two steps. You need to find minimum cost to reach the top of the

2018-05-03 19:27:57 113

原创 821. Shortest Distance to a Character

Given a string S and a character C, return an array of integers representing the shortest distance from the character C in the string.Example 1:Input: S = "loveleetcode", C = 'e'Output: [3, 2, 1, 0, 1

2018-05-02 22:30:33 297

原创 796. Rotate String

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, if A = ‘abcde’, then it will be ‘bcdea’ after one sh

2018-05-01 22:40:32 177

原创 ubuntu16.04 pcl安装教程

pcl下载，网址https://github.com/PointCloudLibrary/pcl 使用git命令或者直接下载zip文件即可。 1.安装依赖 sudo apt-get update sudo apt-get install git build-essential linux-libc-dev sudo apt-get install cmake cm

2018-05-01 16:22:10 12772

原创 693. Binary Number with Alternating Bits

Given a positive integer, check whether it has alternating bits: namely, if two adjacent bits will always have different values.Example 1:Input: 5Output: TrueExplanation:The binary representation of

2018-04-30 20:41:48 145

原创 628. Maximum Product of Three Numbers

Given an integer array, find three numbers whose product is maximum and output the maximum product.Example 1:Input: [1,2,3]Output: 6Example 2:Input: [1,2,3,4]Output: 24Note:The length of the given ar

2018-04-29 09:16:27 121

原创 671. Second Minimum Node In a Binary Tree

Given a non-empty special binary tree consisting of nodes with the non-negative value, where each node in this tree has exactly two or zero sub-node. If the node has two sub-nodes, then this node’s val

2018-04-28 21:53:56 88

原创 674. Longest Continuous Increasing Subsequence

Given an unsorted array of integers, find the length of longest continuous increasing subsequence (subarray).Example 1:Input: [1,3,5,4,7]Output: 3Explanation: The longest continuous increasing subseq

2018-04-27 21:13:46 105

原创 661. Image Smoother

Given a 2D integer matrix M representing the gray scale of an image, you need to design a smoother to make the gray scale of each cell becomes the average gray scale (rounding down) of all the 8 surrou

2018-04-26 07:41:04 84

原创 657. Judge Route Circle

Initially, there is a Robot at position (0, 0). Given a sequence of its moves, judge if this robot makes a circle, which means it moves back to the original place.The move sequence is represented by a

2018-04-25 07:47:04 91

原创 645. Set Mismatch

The set S originally contains numbers from 1 to n. But unfortunately, due to the data error, one of the numbers in the set got duplicated to another number in the set, which results in repetition of on

2018-04-24 08:21:36 192

原创 637. Average of Levels in Binary Tree

Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array. Example 1:Input: 3 / \ 9 20 / \ 15 7Output: [3, 14.5, 11]Explanation:

2018-04-23 19:37:56 172

sample.pcd

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