Help re-applying after Uk visit visa refusal
UK visa refusal on V 4.2 a + c (and sometimes 'e')
Given a file L with one non-negative integer per line and text file F, what would be a fast way to keep only those lines in F, whose line number appears in file L?  Example:  $ cat L.txt 1 3  $ cat F.txt Hello World Hallo Welt Hola mundo  $ command-in-question -x L.txt F.txt Hello World Hola mundo   I'm looking for a command that can handle a file L with 500 million or more entries; file L is sorted numerically.  Note: I'm halfway through an implementation for a command-in-question but I just wondered, whether one might be able to use some Unix tools here as well.    Update: Thank for all the answers, I learned a lot today! I would like to accept more one answer, but that's not possible. Why is it bad to log in as root? I've often come across posts on forums or other websites where you see people joking in such a manner about running/logging in as root as if it's something awful and everyone ought to know about it. However, there isn't much that a search reveals on the matter.   It may be widely known to Linux experts, but I really don't know why. I remember always running as root when I first tried Linux years ago (Redhat and Mandrake) and don't remember running into any problems because of that.   There are actually some distros that have a bright red background with alert signs all over it as wallpaper for the root user (SuSe?). I still use the "Administrator" account for regular use on my Windows installation and haven't ever run into any problems there either. How can I access the apache basic-auth username in a PHP script? Suppose Pat is male. Which one is correct?     I found out Pat is male.      I found out Pat was male.   Does the following change make any difference?     She said Pat is male.      She said Pat was male.   Suppose you created a mathematical model. When you are describing a result, which one (or neither) is correct?     The model analysis shows that the equilibrium is stable.      The model analysis showed that the equilibrium is stable. Installing Wi-Fi driver for Realtek Semiconductor RTL8723DE Device [10ec:d723] How do I install Wi-Fi drivers for Realtek RTL8723DE device in Ubuntu 16.04?  lspci -v | grep -i network 02:00.0 Network controller: Realtek Semiconductor Co., Ltd. Device d723 How to encode the filename parameter of Content-Disposition header in HTTP? Web applications that want to force a resource to be downloaded rather than directly rendered in a Web browser issue a Content-Disposition header in the HTTP response of the form:  Content-Disposition: attachment; filename=FILENAME  The filename parameter can be used to suggest a name for the file into which the resource is downloaded by the browser.  (Content-Disposition), however, states in  (The Filename Parameter) that the file name can only use US-ASCII characters:     Current [RFC 2045] grammar restricts   parameter values (and hence   Content-Disposition filenames) to   US-ASCII.  We recognize the great   desirability of allowing arbitrary   character sets in filenames, but it is   beyond the scope of this document to   define the necessary mechanisms.   There is empirical evidence, nevertheless, that most popular Web browsers today seem to permit non-US-ASCII characters yet (for the lack of a standard) disagree on the encoding scheme and character set specification of the file name. Question is then, what are the various schemes and encodings employed by the popular browsers if the file name “naïvefile” (without quotes and where the third letter is U+00EF) needed to be encoded into the Content-Disposition header?  For the purpose of this question, popular browsers being:   Firefox  Internet Explorer  Safari Google Chrome  Opera One thing that made me curious while watching a football game on TV was the numbers that appear on the ground. For instance, there's a "1st &amp; 10" beside one team, but there was a "3rd &amp; 6" a few minutes prior (and I think it was beside the other team). What do these numbers mean? How can I set the drawableRight resource via code? Is there any information in canon to indicate that Dumbledore knew that the Marauders were Animagi? Is there any information in canon (or from JKR) to indicate that Dumbledore knew that three of the Marauders were Animagi?  I can't recall anything, but Harry seems to be firmly convinced that Dumbledore knows "everything that goes on around here," and that assessment seems to be accurate during Harry's years. How best to include other scripts? Is the formula $(\text{ker }A)^\perp=\text{im }A^T$ necessarily true? If $A$ is a $n\times m$ matrix, is the formula $(\text{ker }A)^\perp=\text{im }A^T$ necessarily true?  I'm thinking that rank-nullity would be the simplest and easiest way to prove this, but would applying the definition of linear independence to the components of $(A^T)$ be more illustrative? I'm a bit hung up on this "necessity" issue, and not sure if it has a particular logical meaning in linear algebra. Let $G$ be a group and $H$ a subgroup with $[G:H]=n$. Is it true that $x^n\in H$ for all $x\in G$?   Remarks. The answer is positive whenever $H$ is normal, e.g., for $n=2$. In general, by using the normal core of $H$, one can find an $m\ge 1$ such that $x^m\in H$ for all $x\in G$. I'm currently reading a little deeper into the Axiom of Choice, and I'm pleasantly surprised to find it makes the arithmetic of infinite cardinals seem easy. With AC follows the Absorption Law of Cardinal Arithmetic, which states that for $\kappa$ and $\lambda$ cardinal numbers, the larger infinite and the smaller nonzero, then $\kappa+\lambda=\kappa\cdot\lambda=\max(\kappa,\lambda)$.  I was playing around with the equation $k+\aleph_0=\mathfrak{c}$ for some cardinal $k$. From the above, it follows that $\mathfrak{c}=k+\aleph_0=\max(k,\aleph_0)$, which implies $k=\mathfrak{c}$.  I'm curious, can we still show $k=\mathfrak{c}$ without the Axiom of Choice? Is it maybe possible to bound $\mathfrak{c}-\aleph_0$ above and below by $\mathfrak{c}$? But then I'm not quite sure such algebraic manipulations even mean anything, or work like that here. Certainly normal arithmetic does not! Thanks. Is it possible to dynamically set Views' pager settings? Say for instance, you have a view that displays when viewing a certain node type, but you want the pager settings to be different for each individual node. I was thinking of making a CCK field like "pager setting" and then give it an integer option of x-y. But I don't know if it's possible to somehow dynamically plug that field into the Views' settings. Or is there another way to do this maybe? When I need to generate unique id's based on some information hashing is typical choice. However, sometimes that id needs to be of a particular size.  I've seen a lot of schemes (HMAC-MD5-96 in SSH, CGA in SeND for IPv6) that use a portion of a hash, so I'm thinking it might be alright to use it that way.    Which properties of a hash are preserved and which do not apply anymore?  Obviously, with less bits, the chance of collision goes up, but can I still rely on the partial hash for uniform character distribution?  What about the ?  I'm guessing that if a hash modifies the entire hash upon the smallest change to the input, that would imply that a portion of that hash would be equally well changed.  Am I thinking about this correctly?  Also, would these behaviors be different for different hashing algorithms? I'm stuck with the proof of the following:  Suppose that $(s_n)$ converges to $s$, $(t_n)$ converges to $t$, and $s_n \leq t_n \: \forall \: n$. Prove that $s \leq t$.   I've tried starting with $s_n \leq t_n \: \forall : n$ and the definitions of each limit (i.e. $|s_n - s| \leq \epsilon \: \forall \: n &gt; N_1$), but I'm not really getting very far. Any help is appreciated! Markdown for ordered lists, starting with zero? I see that you can create an ordered list using Markdown notation like the following.  1. line 1 2. line 2 3. line 3 ... N. line N   The Markdown content supports starting each line with any arbitrary number and reorders the list starting with 1. I'd like to start an ordered list with zero. My use case for zero would be in describing capture groups from regular expressions where group zero always returns the entire string. So I'd like to display something like this:  # Groups 0. Entire string 1. The first capture group you were looking for 2. The second capture group 3. The third group with the string I heart Kittens   Markdown instead reorders the group and forces the ordered list to start at 1:    Trying to force the issue with inline HTML: &lt;ol start="0"&gt; or &lt;ol&gt;&lt;li value="0"&gt;entire string&lt;/li&gt;&lt;/ol&gt; doesn't work either. Any ideas on how I can create ordered list starting with zero?  If it's not possible to do so, then this is a feature-request. "big enough to do this" My question is what is the difference among these three sentences.   He is big enough to do such  heavy works. He is not big enough to do such heavy works. He is small enough to do such  heavy works.   I am so much confused between 2 and 3.Also, I don't get what the 3rd one means. Is there any way to tell Google to display the updated title instead of displaying the old blog title in search results? Custom toolbar location XP A few years ago Umber Ferrule wrote that the toolbars in the taskbar are defined in   HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Streams.   This looks very plausible but cannot be the entire story.  Deleting this key will in no way affect the taskbar and on rebooting the system the key magically reappears.  Why do I want to know?  Simple.  I would like to export the key to a reg. file as a convenient backup.