Useful Tools I Use
k2pdfopt A tool, transforms pdf files to easy-read pdf in mobile device. K2pdfopt optimizes PDF/DJVU files for mobile e-readers (e.g. the Kindle) and smartph...
Archive by Year
2017
Math Related Things
Relation between Density and Histrogram funcion Given , where is the density function of , and the width of each bin , we can produce histrogram function...
Linux Management
What’s Ctrl-C, Ctrl-D…
famous algorithm
Median of medians The optimal algorithm selecting kth largest element,with linear time complexity Reference: https://en.wikipedia.org/wiki/Median_of_medians
common sense
Foot <-> Inch <-> Centimeter
My Notes about C++
Funny tricks #define foo(...) printf(__VA_ARGS__);
STL container
Sequence container: array Just like int a[], it’s a simple wrapper.
Prove O(log(a+b))=O(log(a)+log(b))
To prove: We need to have: is equivalent to:
About Ordering Theory
Properties of various ordering
How to onekey to restart a program in Windows
Sometimes, I need to restart a program frequently. So I write this script, to easily quckly restart a program. Here are steps: Save following code as rest...
How to setup putty to auto connect to your computer
How to make putty(in Win7) auto connect to your computer(Linux)? Let say, we have a windows computer A, and a linux computer B. And We want use putty to auto...
Collaborating by sharing screen or terminal
tmate Tmate is an instant terminal sharing application.
Linux: Use trash instead of rm
Why use trash instead of rm ? If you wrongly rm sth, it can’t recovered.
2016
Encoding Problems
Please refer to: EncodingProblem
Things Inside Conversion Between Types in C++
One day, I’m curious about what really happens when converting variables to different types in C++? So I write the following program to find the truth. If yo...
Auto Login WIFI using Tasker in Android
How to auto connect to a wifi that needs login manually?
Youtube video not works(For Chinese)
If you have set up the web proxy, and find out youtube video still not work, you may configure to proxy the following sites: youtube.com googlevideo.com
Learning Python
Learning Python Reference Url: https://docs.python.org/3.4/tutorial/
Understand output of diff
Abstract Explanation The normal output format of diff consists of one or more chunks of differences, each hunk shows one area where two files differ. Normal...
2015
Jobs In Linux
The general job control commands in Linux are:
How to synchronize time across a cluster?
A basic step about synchronizing time using ntp. Install Ntp Server in master computer. Run following commands in master computer: sudo apt-get instal...
How to setup ssh tunnelling in windows
Situation You have a middle computer A, says OS is win7, the middle computer A connects to a inside computer B, which has access to inner network. And each t...