problems with apt-get install
Permission denied, are you root?
Trying to overwrite ... which is different from other instances of package I tried to upgrade Intel graphics in ubuntu 16.10 using the official installer. The last stage of unpacking libcairo2 produces an error (see figure).  When I do upgrade I get the same error also:   Preparing to unpack .../0-libcairo2_1.15.2-0intel1_amd64.deb ... Unpacking libcairo2:amd64 (1.15.2-0intel1) over (1.15.2-0intel1) ... dpkg: error processing archive /tmp/apt-dpkg-install-aYhdFd/0 libcairo2_1.15.2-0intel1_amd64.deb (--unpack): trying to overwrite shared '/usr/share/doc/libcairo2/changelog.Debian.gz', which is different from other instances of package libcairo2:amd64 Preparing to unpack .../1-libcairo2_1.15.2-0intel1_i386.deb ... Unpacking libcairo2:i386 (1.15.2-0intel1) over (1.15.2-0intel1) ... dpkg: error processing archive /tmp/apt-dpkg-install-aYhdFd/1-libcairo2_1.15.2-0intel1_i386.deb (--unpack): trying to overwrite shared '/usr/share/doc/libcairo2/changelog.Debian.gz', which is different from other instances of package libcairo2:i386 Errors were encountered while processing: /tmp/apt-dpkg-install-aYhdFd/0-libcairo2_1.15.2-0intel1_amd64.deb /tmp/apt-dpkg-install-aYhdFd/1-libcairo2_1.15.2-0intel1_i386.deb E: Sub-process /usr/bin/dpkg returned an error code (1)   It seems that there is a conflict in thelibcairo releases; if yes, how to resolve it ? A well-supported wireless PCI adapter for Ubuntu 12.04? How to find out if my system is i386 or x86_64 before installing Ubuntu? I am using Windows as of now and want to install Ubuntu. I want to find out if my system is i386 or x86_64? How do I do that? Common screen resolution? I'm developing a web application which is quite information heavy. This means that every pixel available in the screen for display helps a lot, to avoid the UI looking too cluttered and to display relevant data.  I was wondering: which is the "common" screen resolution? Years ago it was something like 1024&times;768, but nowadays it must be something much higher. I can't rely on what I use as I'm a developer and I probably have bigger screens and resolution than the average Joe user.  So, where can I find the currently recommended resolution for webapps? Can anyone make me understand in simple language why the second condition for being an Euclidean domain is superfluous ?  Why $v(a)  \leq v(ab)$ is not needed?  How we can deduce from the first one? How do I add SSL to a .net application that uses httplistener - it will *not* be running on IIS Most recent edits in bold I am using the .net HttpListener class, but I won't be running this application on IIS and am not using ASP.net.  This  describes what code to actually use to implement SSL with asp.net and  describes how to set up the certificates (although I'm not sure if it works only for IIS or not).    The class documentation describes various types of authentication (basic, digest, Windows, etc.) --- none of them refer to SSL.  It does say that if .  Is this going to be a one line property setting and HttpListener figures out the rest?    In short, I need to know how to set up the certificates and how to modify the code to implement SSL.  Although it doesn't occur when I'm trying to access HTTPS, I did notice an error in my System Event log - the source is "Schannel" and the content of the message is:     A fatal error occurred when attempting   to access the SSL server credential   private key. The error code returned   from the cryptographic module is   0x80090016.   Edit: Steps taken so far   Created a working HTTPListener in C# that works for HTTP connections (e.g. "" Created a certificate using makecert.exe Added the certificate to be trusted using certmgr.exe Used Httpcfg.exe to listen for SSL connections on a test port (e.g. 8090) Added port 8080 to the HTTPListener via listener.Prefixes.Add("); tested an HTTP client connection, e.g. (") in a browser and receive correct return tested an HTTPS client connection, e.g. (") in a browser and receive "Data Transfer Interrupted" (in Firefox) debugging in visual studio shows that the listener callback that receives the requests never gets hit when the HTTPS connection starts - I don't see any place that I could set a breakpoint to catch anything else earlier. netstat shows that listening ports are open for both HTTPS and HTTP.  the HTTPS port does go to TIME_WAIT after a connection is attempted.  and  don't catch any of the traffic, I guess it doesn't get far enough in the process to show up in those HTTP analysis tools   Questions   What could the problem be?  Is there a piece of .Net code I am missing (meaning I have to do more in C# other than simply add a prefix to the listener that points to HTTPS, which is what i have done) Have a missed a configuration step somewhere?  What else might I do to analyze the problem? Is the error message in the System Event log a sign of the problem?  If so how would it be fixed? Convergence of $\sum_{n=1}^{\infty}{\sqrt[n]{n}-1 \over n}$ I am trying to conclude about the convergence of $$\sum_{n=1}^{\infty}{\sqrt[n]{n}-1 \over n}$$ If I take ${\sqrt[n]{{\sqrt[n]{n}-1 \over n}}}= {\sqrt[n]{\sqrt[n]{n}-1} \over \sqrt[n]{n}}$ this looks like it converges to $0$ but I am suspicious about the numerator. At the same time, other techniques I know like the ratio test, $n(\sqrt[n]{n}-1)$ and comparisons don't yield meaningful results. Any hints? Casting two cantrips, both modified by metamagic? Can you cast one cantrip, modifying it with "Twinned Spell" (Fire Bolt) to target 2 creatures, and then cast another cantrip as a Bonus Action (Fire Bolt), using "Quickened Spell" to target one of the previous creatures or another creature? Why is using a wild card with a Java import statement bad? cgi and tomcat im trying to run a cgi script (.cgi) with tomcat. I am getting the below error and cant find out whats wrong. I know i should really use apache and mod proxy but this really isnt my area of expertise so im taking the easy way out!  Thanks for any help.   java.io.IOException: Cannot run program "perl" (in directory "C:\Java\tomcat\webapps\my_app_name\WEB-INF\cgi"): CreateProcess error=2, The system cannot find the file specified     java.lang.ProcessBuilder.start(ProcessBuilder.java:459)     java.lang.Runtime.exec(Runtime.java:593)     java.lang.Runtime.exec(Runtime.java:431)     org.apache.catalina.servlets.CGIServlet$CGIRunner.run(CGIServlet.java:1705)     org.apache.catalina.servlets.CGIServlet.doGet(CGIServlet.java:597)     javax.servlet.http.HttpServlet.service(HttpServlet.java:627)     javax.servlet.http.HttpServlet.service(HttpServlet.java:729)     org.tuckey.web.filters.urlrewrite.UrlRewriteFilter.doFilter(UrlRewriteFilter.java:738)     org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:416) What is the physical explanation for energy transport in simple electrical circuits? Keeping it simple, what is the physics approach to a current in a wire connected to a battery? How does the electric field behave?  I've read somewhere that, contrary to the common conception, electrons don't really flow as water in a hose so, what is really going on there? How is energy transported at the speed of light if electrons don't flow like very fast water? How can I create an association list from 2 lists? I have a Canon Powershot A710 and I previously had a previous Powershot A-series model. I love them due to the high amount of control they offer. Sadly, they both suck in low light conditions, their flash is very unresponsive, and the camera takes several seconds preparing itself for the next shot after a flash shot. And even then, the pictures they take in low light/flash are as bad as good are those with good light.  I'd like a camera which gives a lot of control options, but what do I need to look for to find one that's great in low light, with or without flash? How to make a grid-to-sphere animation like this? "I", "me" and "myself" Possible Duplicate:           What is correct? We are a family of four: my father, my mother, my brother and me. or We are a family of four: my father, my mother, my brother and I. or We are a family of four: my father, my mother, my brother and myself. We have a pool of N number of balls.  There are: A number of white balls (W), B number of green balls (G), C number of blue balls (B), and D number of pink balls (P)  In how many ways (combinations) we can pick X number of balls from this pool? Is there a formula for something like this?  This is similar to combinations with replacement, but there are limitations to how many times a certain object can be replaced. "Closed" (square) root symbol I found a cool trick in the  which allows the square root sign to be altered such that it &quot;closes&quot; over its contents. Here's an example:  (&quot;closed&quot; root on the left, normal one on the right) The way they do this is as follows: % New definition of square root: % it renames \sqrt as \oldsqrt \let\oldsqrt\sqrt % it defines the new \sqrt in terms of the old one \def\sqrt{\mathpalette\DHLhksqrt} \def\DHLhksqrt#1#2{% \setbox0=\hbox{$#1\oldsqrt{#2\,}$}\dimen0=\ht0 \advance\dimen0-0.2\ht0 \setbox2=\hbox{\vrule height\ht0 depth -\dimen0}% {\box0\lower0.4pt\box2}} The cool thing is that (as far as I've tested it) this works regardless of the math font and with pdftex as well as xetex. However what is not possible is mulitple roots, such as \sqrt[3]{a}. Those produce incorrect output when this &quot;trick&quot; is being used. So my question is, is somebody able to tweak this code so that it works for multiple roots as well? I am trying to write the Euclidean algorithm in the following way:  $A = \lfloor A \div B \rfloor \times B + (\text{remainder of}) \: A \div B $   Now is there any symbol I can use  to say "remainder of A $\div$ B"? I know that in the C programming language there is the operator % for modulus; is that a valid symbol in maths? Can I write A % B? Or is there some other way? Looking for a simple proof that groups of order $2p$ are up to isomorphism $\mathbb{Z}_{2p}$ and $D_{p}$ . I'm looking for a simple proof that up to isomorphism every group of order 2p (p prime) is either $\mathbb{Z}_{2p}$ or $D_{p}$ (The Dihedral group of order 2p).  I should note that by simple I mean short and elegant and not necessarily elementary. So feel free to use tools like Sylow Theorems, Cauchy Theorem and similar stuff.  Thanks a lot! What is the product of the empty set? Give:  $fn(S)=\prod_{x\in S}x$  what is:  $fn(\emptyset)$  I can see reason that it would be defined as 1 or 0.    Note: I thought about restricting the domain of $S$ but that would make the problem less general. If there is no general answer then answers for restricted domains would be valid.