Object Oriented Programming in C++ - Header Files
Why have header files and .cpp files?
I know that $S_n$ is generated by a number of things, like all transpositions, all transpositions of the form $(1\,a)$, the transpositions $(1\,2),(2\,3),\dots,(n-1\, n)$, and  just the two elements $(123\dots n),(1\,2)$.      Suppose $n$ is prime. If you just have $(123\dots n)$ and some arbitrary transposition $(a\, b)$, how does this also generate $S_n$?    Can you somehow get to $(1\,2)$ or reduce it to some other previous case? I'm using NetBeans, trying to change the familiar Java coffee cup icon to a png file that I have saved in a resources directory in the jar file.  I've found many different web pages that claim they have a solution, but so far none of them work.  Here's what I have at the moment (leaving out the try-catch block):  URL url = new URL("com/xyz/resources/camera.png"); Toolkit kit = Toolkit.getDefaultToolkit(); Image img = kit.createImage(url); getFrame().setIconImage(img);   The class that contains this code is in the com.xyz package, if that makes any difference.  That class also extends JFrame.  This code is throwing a MalformedUrlException on the first line.  Anyone have a solution that works? The reason that I ask is because this is happening to LiDAR, and I am inclined to use lidar because it is easier to read. $\mathbb Z^n/\langle (a,...,a) \rangle \cong \mathbb Z^{n-1} \oplus \mathbb Z/\langle a \rangle$ Change Proxy Settings In Ubuntu I want to use the Ubuntu Software Center to install software, but I cannot download them.  How can I give my proxy settings in Ubuntu terminal (just like we use cmd in Windows to choose IE proxy settings)? When I am writing I often come across the words "around" and "round." I was wondering what is different between them, and how they would be used in different contexts. Automatic reboot after ubuntu freeze? How Can I Do It? What is a use case where one would use an SObject as a Map key? My Windows 7 has suddenly stopped displaying Unicode symbols For some strange reason, my computer suddenly doesn't show certain unicode characters anymore! I have no idea what happened.  Affected applications include Windows Explorer (should be Japanese characters), Google Chrome (should be a heart), and Winamp (should be stars):      Russian, German etc. characters are displayed normally. Chrome also displays Japanese script on websites, but not in the GUI. How can I fix it?     TL;DR: A workaround is to put a shortcut with a Unicode name on the desktop so that explorer.exe is the first process to display a Unicode string after booting.     Update: I have tried to use System Restore to fix it. I needed to go back in time quite a while because the most recent restore points didn't solve it so I used one from the middle of November. After that restore, Unicode symbols were displayed again. Then I updated my system with Windows Update again because those were removed during the restore. After that, the error occurred again! I then did a restore to a point before my new updates, but the error persists, and the old restore point (which I used before) is gone and there are currently no other snapshots of the system. Any suggestions on what to do now?  Update 2: I could find a workaround:      Control Panel → Region and Language → Administration → Change Language for Unicode-incompatible programs to Japanese (Japan).    All mentioned programs display their symbols correctly again. However, I don't consider this a fix because these programs are not usually Unicode-incompatible, and it also leads to some (non-serious) artifacts in some programs. I still welcome an answer that tells me what went wrong here and how to fix the issue.  Update 3: I think I have isolated the particular Windows Update which causes the error. It is . I have installed all other updates except this one, and the error did not occur again.  Update 4: The true origin of this problem was Chrome, see accepted answer. Workaround: put shortcut with Unicode name on desktop so that explorer.exe is the first process to display a Unicode string after booting. I can't really remember how long ago it was, but I think the book was marketed towards children/teens.  All I remember is the basic premise of the story.  Some story about these unusual little blue electric critters that only certain people could see, and these kids took it upon themselves to go about destroying them since they fed off energy or something like that.  Not sure whether they fed off people or off electricity... or both maybe?  I think the dominant method of destroying them was an electric baton that was taken from law enforcement.  I wanna call them buzz batons, but that's probably thanks to Artemis Fowl. Searching for Google contacts not in Groups Possible Duplicate:          In Google Contacts, I've had Groups set up which look like this: All Contacts.. Family.. School.. Work.. etc.  Each contact I have is assigned to All Contacts. In addition, it is assigned to at least one more Group.  Sometimes when I add contacts, I forgot to bucket them in the respective groups, so I was wondering is there anyway I could do a search for contact that belongs toAll Contact-group, but does not belong to any other group ? Functional Equation (no. of solutions): $f(x+y) + f(x-y) = 2f(x) + 2f(y)$ Find all the functions $f\colon\mathbb{Q} \to \mathbb{Q}$ such that $f(x+y) + f(x-y) = 2f(x) + 2f(y)$, for all rationals $x,y$. I recently put a bounty on a question regarding the . I did this as the only two answers on that page are not satisfactory and I wish to encourage a tractable answer.  I am concerned that when the bounty period expires, if I do not select an answer for the bounty that it may be awarded automatically to one of these speculative and unsatisfactory answers. How might I prevent that? I could put an answer of my own stating "no satisfactory sources are available" and award the bounty to that, however I feel that there should be a better way.  I stress that I put the bounty on the question specifically because the current answers are not satisfactory and I do not want to award them. software updater failed to download repository information When I run software updater it says that it failed to download repository information and to check Internet connectivity.  I have Internet connectivity.  How do I fix this?  editing to add content of sources,list:  sorry I can't figure out how to paste in the content of sources.list without making a huge mess.  Some of it previews as really large bold print.  I tried to follow the block quoting and code rules but it is a huge mess anyway. While reading a book, I came across the word I'd've, as in:     I'd've argued against it.   While it was obvious what it meant, it left me puzzled. Is I'd've a proper word? How can I remove malicious spyware, malware, adware, viruses, trojans or rootkits from my PC? What should I do if my Windows computer seems to be infected with a virus or malware?  What are the symptoms of an infection? What should I do after noticing an infection? What can I do to get rid of it? how to prevent from infection by malware?   This question comes up frequently, and the suggested solutions are usually the same. This community wiki is an attempt to serve as the definitive, most comprehensive answer possible. Feel free to add your contributions via edits. Maximum and minimum distance of two points Consider six distinct points in a plane. Let $m$ and $M$ denote respectively the minimum and the maximum distance between any pair of points.  Show that $M/m \geqslant \sqrt{3}$. What is the function of the "Sticky edges" on/off setting in displays? I have installed Ubuntu 12.04 (Precise Pangolin). If I open System Settings &gt;&gt; Displays there is a new (?) on/off button for a setting named Sticky edges.  Can someone tell me what this setting is supposed to control? Industry standard file format deliverables for logos? Using Elseif Conditional Statement in QGIS Field Calculator?