# 老头儿

​ 村子里住着一个老头儿，老头儿是个瘸腿。没人记得老头儿是什么时候来这个村子的，也没人知道他到底叫什么，年龄有多大。老头儿看起来很老，黄褐色的皮肤上有一道道沟壑，一看就是饱经沧桑的样子，所以村子里的人都叫他老头儿。

# Linear Algebra Week2 homework

For This chapter, I mainly learnt the nature of determinant and how to expand the determinant due to its row or line.

# Reboot phone on computer

I accidentally put my phone in the sea once, and then keep the power on and it broke down. After fixing it, the power off/on button is broken, so I can’t turn off or reboot my phone by pushing the button. So, I use this way:

# Basemap learning

Since I have already introduced Basemap and how to install , I’ll start it directly.

# CodeForeces-1301 A Three Strings

A. Three Strings
time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

# Draw map with Color

Last article, we learned how to draw a uncolored map with python. Now, we are going to fill our country with beautiful colors.

# CSS-Rules

Some of the basic rules of CSS and also a learning and reviewing Records of CSS.

# HTML-Tags

Some of the most often used tags of HTML. And it’s also a record of learning process.

# CodeForces-1300 B Assigning to Classes

B. Assigning to Classes
time limit per test: 2 seconds
memory limit per test: 256 megabytes
input: standard input
output:standard output

# CodeForces-1300 A Non-zero

A. Non-zero
time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

# Preparation

Before you start to draw maps with python, you first need to install basemap and pyshp. Click here to see how to install basemap . And the following command to install pyshp

# Install Basemap of Python(Linux)

Basemap is a plug-in of matplotlib. Matplotlib is a drawing library that helps to draw data in multiple ways using python. And Basemap is used to draw maps. The followings are steps to install basemap.

# CodeForces-1296 C Yet Another Walking Robot

C. Yet Another Walking Robot
time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

# CodeForces-1296 A Array with Odd Sum

A. Array with Odd Sum
time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

# Git Commands

Just because I want to solve a problem while setting my gitee(It needs to input user name and password every time I deploy my Blog), a friend let me study git first so that I can understand what the bug is telling about!!!!

# CodeForces 1295 A Display The Number

A. Display the Number
time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

# Make previous windows blog available on Linux

While using windows, I have already had a blog and using hexo system. And my blog is on my mechanical hard disk. I want it to be accessible while using Linux.

There are two steps to make it.

# Absolute path and Relative path

There are two ways to represents a directory, Absolute path and Relative path.

path start start sign
Absolute root directory /
Relative current directory ~

# How to mount mechanical hard disk on Linux

I’ve met a new problem recently: I switched into Linux but my Blog folder is under my mechanical hard disk. I want my Blog folder available to be achieved by command not manually.

# Spawn-Failed

Recently, I’ve met a problem like this when I deploying my blog. hexo d gets error.

# CodeForces-1293B JOE is on TV!

B. JOE is on TV!
time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

# CodeForces-1293A ConneR and the A.R.C. Markland-N

A. ConneR and the A.R.C. Markland-N
time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

# Sorts

Here are some sorting ways and I use many data to test and compare. Just to illustrate the property of each algorithm.

# CodeForces-1288 B Yet Another Meme Problem

B. Yet Another Meme Problem
time limit per test: 1 second
memory limit per test: 256 megabytes
input: standard input
output:standard output

time limit per test: 2 seconds
memory limit per test: 256 megabytes
input: standard input
output:standard output

# Mathematical Statistics Concepts

（1）总体与个体

​ a. 一批灯泡的全体组成一个总体，其中每一个灯泡都是一个个体。

​ b. 一个随机变量X或其相应的分布函数$F(x)$成为一个总体。