i have an assignment where i have to make a program that reads input and evaluates whether or not it is a palindrome until the user terminates. i am having issues with the while loop. it works like it should upon first input, but then when it re-enters the loop, it always says it is not a palindrome, even when it is.  Scanner in;     in = new Scanner (System.in);      String original = "";       //variable for user input     String original2 = "";      //variable to help make input case insensitive     String reverse = "";        //variable to compare word in reverse     int length;                 //variable used to      int i;                      //variable used in for loop     //String response = "";      System.out.println("Enter a word to check if it is a palindrome!");      original = in.nextLine();      while (!original.equals("n"))      {         length = original.length();          original2 = original;       //assigning a new variable to hold the input, so as to not change it          original2 = original.toLowerCase(); //converting input to all lower case using the holder variable           for (i = length -1; i &gt;= 0; i--)    //for loop reversing the word to check for palindrome status         {             reverse = reverse + original2.charAt(i);         }          if (original2.equals(reverse))      //if statement determining output if palindrome is true or not         {             System.out.println(original + " is a palindrome");         }         else         {             System.out.println(original + " is not a palindrome");         }          System.out.println("Enter another word or enter 'n' to end");   //allowing to continue         original = in.nextLine();      }  System.out.println("thank you!");     in.close(); }   i initially thought that it was an issue with the buffer, but i no longer think that is an issue.   i will really appreciate any help at all
I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?
Proof by induction that if $n \in \mathbb N$ then it can be written as sum of different Fibonacci numbers Proof that every natural number $n\in \mathbb N$, can be written as the sum of different Fibonacci numbers between $F_2,F_3,\ldots,F_k,\ldots$.  For example: $32 = 21 + 8+3 = F_8+F_6+F_4$  Research effort:  The base step it's simple:  Let $k=1$ it can be britten as $k=1=F_2$  For the inductive step I considered:  Let $k = k  F_2 =F_2+F_2+\cdots+F_2 = \sum_{i=2}^w a_iF_i, a_i =\{0,1\} $  Then if $k$ suffice I want to see if $k+1$ suffices too... But I'm not realy seeing how to use the inductive hypothesis, so I assume It's wrong.  Any thoughts on which can the inductive step be? Why is removing instationarities a good thing when trying to forecast a time series? Python: Finding differences between elements of a list How to install with Wubi when it says "Could not retrieve the required disk image files"? I tried to install Ubuntu 12.10 with the Wubi installer while running Windows, because my PC does not accept my BootCD as a bootable medium.  But Wubi showed me this error:  Ubuntu-Installationsprogramm (X) Ein Fehler ist aufgetreten: Could not retrieve the required disk image files Weiter Informationen finden Sie in der Protokolldatei: c:\users\username\appdata\local\temp\wubi-12.10-rev273.log   What can I do, because I want to get rid of my Windows 7 and use the way better Ubuntu 12.10?  Thanks for your huge answer, now my next problem after trying to install wubi with the .iso is, that the same error shows up again and i am not shure which part of the errorreport you need.  Can you tell me? Because i'm not that good at linux. How do I enable Scroll Lock? I need to enable scroll lock so I can toggle lights on my keyboard. This works on Arch.Funny thing it doesn't work on Ubuntu.    $ xmodmap -e ‘add mod3 = Scroll_Lock’ xmodmap:  unknown command on line commandline:1 xmodmap:  unable to open file 'mod3' for reading xmodmap:  unable to open file '=' for reading xmodmap:  unable to open file 'Scroll_Lock’' for reading xmodmap:  4 errors encountered, aborting. How can I prove $\lim_{n \to \infty} \frac{n^2}{2^n}=0$ How can I prove $\lim_{n \to \infty} \frac{n^2}{2^n}=0$  I tried to use $\mid \frac{n^2}{2^n} - 0 \mid &lt;\epsilon $ However, because of $n^2$ I cannot use it. Also, I tried to use ratio test and I got $\lim_{n-&gt;\infty}\frac{(n+1)^2}{2}\frac{1}{n^2}$, but after that one, I dont know how to get limit &lt; 0  I have no idea to solve this problem.   I can also use a squeez lemma, but dont know how to apply to this question. In bash, read after a pipe is not setting values With ksh I'm using read as a convenient way to separate values: $ echo 1 2 3 4 5 | read a b dump $ echo $b $a  2 1 $  But it fails in Bash: $ echo 1 2 3 4 5 | read a b dump $ echo $b $a     $  I didn't find a reason in the man page why it fails, any idea? Typesetting a full citation whose title ends with a word in braces I am using Biblatex and need to typeset full citations in my document text, so I'm using .  While it works correctly most of the time, it has trouble with Biber/BibTeX entries where the last word of a field is enclosed in braces (to force capitalization).  In these cases, \longfullcite may fail to properly capitalize the following word.  Take the following example:  \documentclass{article}  \usepackage{biblatex} \makeatletter \newcommand{\tempmaxup}[1]{\def\blx@maxcitenames{\blx@maxbibnames}#1} \makeatother \DeclareCiteCommand{\longfullcite}[\tempmaxup]   {\usebibmacro{prenote}}   {\usedriver      {\DeclareNameAlias{sortname}{default}}      {\thefield{entrytype}}}   {\multicitedelim}   {\usebibmacro{postnote}}  \usepackage{filecontents}  \begin{filecontents}{test.bib} @inproceedings{blow2015,   author       = {Blow, Joe},   title        = {{GNU} loves me},   year         = 2015,   booktitle    = {Proceedings of Some Conference}, }  @inproceedings{blow2016,   author       = {Blow, Joe},   title        = {I love {GNU}},   year         = 2016,   booktitle    = {Proceedings of Some Conference}, } \end{filecontents}  \addbibresource{test.bib}  \begin{document} \nocite{*} \noindent \longfullcite{blow2015}\\ \longfullcite{blow2016} \printbibliography \end{document}   Here is the output:    Note the inconsistent capitalization of the word "In" produced by the two \longfullcite commands.  By contrast, the citations emitted by \printbibliography correctly capitalize "In" for both entries.  What is causing this inconsistency and how can I fix or work around it (preferably by changing the definition of \longfullcite rather than changing the .bib file)? Comparing two byte arrays in .NET How to typeset the symbol “^” (caret/circumflex/hat) Change the passphrase of an ecryptfs directory CW complex such that action induces action of group ring on cellular chain complex. Let $X$ be a space that satisfies the hypotheses used to construct a universal cover $\overline{X}$. Let $\pi = \pi_1(X)$ and consider the action of the group $\pi$ on the space $\overline{X}$ given by the isomorphism of $\pi$ with $\text{Aut}(\overline{X})$. Let $A$ be an abelian group and let $\mathbb{Z}[\pi]$ act trivially on $A$, $a \cdot \sigma = a$ for $\sigma \in \pi$ and $a \in A$.  Now, assume that $X$ is a CW complex. How do I see that $\overline{X}$ is a CW complex such that the action of $\pi$ on $\overline{X}$ induces an action of the group ring $\mathbb{Z}[\pi]$ on the cellular chain complex $C_*(\overline{X})$ such that each $C_q(\overline{X})$ is a free $\mathbb{Z}[\pi]$-module and$$C_*(X; A) \cong A \otimes_{\mathbb{Z}[\pi]} C_*(\overline{X})?$$ How can I read my hard drive’s SMART status in Windows 7? How can I read the  S.M.A.R.T. state of my HDDs while using Windows 7, either automatically or manually? Is using Gravatar a security risk? This has been . It is unfortunate the accepted answer is so far from reality.   There are some facts:    's MD5 hash is an unsalted MD5 hash of an email address. A 3rd party could harvest every MD5 hash for every user's email on Stack Overflow.  The 3rd party could store all the hashes in a lookup table Email addresses are usually of a very particular format The attacker could start with a brute force of @gmail.com followed by @yahoo.com, etc. The attacker has the advantage that he/she could attack a huge set of emails in one go. So instead of needing to brute force every email individually the attacker can brute force in bulk.   The algorithm is quite simple, calculate a "random" MD5, look it up in the lookup table.       Is Gravatar a big enough security risk to warrant caching images locally?     Examples:    Someone could harvest about 50k email addresses quite easily and shoot off a bogus promotion from Stack Overflow to all the users. A spammer/stalker/generic evil guy can tie you identity to all the rest of the sites that use Gravatar. Is there any way to get the number of pending chat request on omni channel? I have a requirement to get the number of pending chat request in the omni channel.  I have set the presence configuration capacity to 5 so that an agent can have only 5 chat requests. if a case is solved agent will get one of the pending chat request. But right now i can't see the number of pending request.     Lets say i have 10 pending request in the queue, but i don't have any numbers to see how many are pending in the queue.   Is there any way that can show the pending chat requests in the queue? Equivalence principle question I understand the  as "The physics in a freely-falling small laboratory is that of special relativity (SR)." But I'm not quite sure why this is equivalent to "One cannot tell whether a laboratory on Earth is not actually in a rocket accelerating at 1 g". At work we have a Domain Controller running Server 2008 R2. Our desktop support group has the ability to join computers to the domain using their network credentials. We are now running into a problem where if the name of the computer that is being joined is the same as an existing computer on the domain, the existing computer will get a "The trust relationship has failed..." error and will not authenticate at all unless someone logs in as a local admin, changes the computer name and rejoins it to the domain.  I want to make it so that Desktop Support can only join computers with unique names to the domain. If the name already exists on the domain the operation should fail. Looking through TechNet it looks like this functionality exists but I can't seem to find out how to enable it.  Any ideas? Making crafted items usable in adventure mode In a map I'm making the player has to survive while locked in a maze. To stop them from breaking out, they will be in adventure mode. However, I still want them to be able to craft items and use them with specified blocks. I have tried several methods already but they all have a flaw.  One method is to have a scoreboard objective called item and giving certain item entities a specific score using something like:  /scoreboard players set @e[type=Item] item 1 {Item:{id:"minecraft:sapling"}}   Then it is possible to select these items with:  /entitydata @e[type=Item,score_item=1,score_item_min=1] {Item:{tag:{CanPlaceOn:["dirt"],HideFlags:24}}}   This works but it requires the item to be dropped, which isn't a problem for saplings, but for tools and other craftable items, it becomes a hassle.  To fix this, I'm currently clearing tools without damage and giving the player a slightly damaged tool in return:  /clear @a minecraft:stone_axe 0 1   /give @a minecraft:stone_axe 1 1 {CanDestroy:["log","log2","leaves","leaves2"],HideFlags:24}   This doesn't work for items without damage values (e.g. torches), but I don't mind these having to be dropped as there aren't too many of these. However, there is another problem. In the nether, the player will have access to an enchantment table and an anvil. This means they can repair enchanted tools, which will cause them to be cleared and replaced with unenchanted ones as soon as they go back to the overworld.  I also thought about using a stat.craftItem scoreboard objective and giving them the usable item if they craft it. However, this would result in the player having a duplicate of every item they crafted, as I think it is impossible to select an item without NBT-data in the /clear command.  Is there any way to make this work? And if not, would it be better to have the player drop all crafted items or have duplicates of them all? I'm using ubuntu 13.10 as htpc. To save some power, i have set it to suspend after 30minutes of inactivity. Before entering suspended state, a popup appears to warn me that computer is about to get put to sleep. This is a little annoyance since it appears when i resume the pc later.   How can i disable this notification for good? How to disable grub menu at boot time in Ubuntu 20.04?