Why does Google prepend while(1); to their JSON responses? Here's my original reply with the new character: $usr = 'Amer/kdb8916' $amer = $null if ($usr -match '\\ ( [^\\]+)$') { $amer = $matches[1] } $amer we could change the command to. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. WebRegular expressions are the default pattern engine in stringr. @rasjani: It depends on the language if you can use that regular expression like I wrote it. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. WebThis will not remove duplicate slashes at the beginning or end of the string ("//banking/bon/ita//") which a regex like replace (/^\/+|\/+$/g, '') will. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, I modified this to remove any number of leading or trailing slashes, by using "+": replace(/^\/+|\/+$/g, ''). Why is 51.8 inclination standard for Soyuz? rev2023.1.18.43170. Or you could use a combination of strrpos and substr, first find the position of the last occurence and then get the substring from that position up to the end. Asking for help, clarification, or responding to other answers. Why did it take so long for Europeans to adopt the moldboard plow? Suppose a string containing this notation should be validated and the components (the letter and the digit) extracted using capture groups. How we determine type of filter with pole(s), zero(s)? I believe this approach is probably easier to understand, after all regexes - in general - are hard to read: NorthWind.ac.uk/Users/Current/IT/Surname, FirstName has a path-like structure (windows How do you access the matched groups in a JavaScript regular expression? Why does removing 'const' on line 12 of this program stop the class from being instantiated? MASL Nov 19, 2015 at 17:27 Add a comment 0 For the sake of completeness: You could Asking for help, clarification, or responding to other answers. Asking for help, clarification, or responding to other answers. Personally, I like Jilbers solution best. Browse other questions tagged. based on @ Mark Rushakoff 's answer the best solution for different cases: c( " aaa"). What is the JavaScript version of sleep()? Any thoughts on how I could do this? Why are there two different pronunciations for the word Tee? How to translate the names of the Proto-Indo-European gods and goddesses into Latin? Edit: but it requires lookbehind, not supported by ECMAScript (Javascript, Actionscript), Ruby or a few other flavors. and the replacement string rev2023.1.17.43168. Some people find this jungle of leaning trees By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Since this is regularly proving useful for others, here's a snippet example As stated in @Archer's answer, you need to double up on the backslashes. Making statements based on opinion; back them up with references or personal experience. Your original question specified the forward slash, but it looks like you're actually dealing with a backslash (ie, "AMER\UserName"). Notes: No parens because it doesn't need any groups - r To learn more, see our tips on writing great answers. How to translate the names of the Proto-Indo-European gods and goddesses into Latin? How to tell if my LLC's registered agent has resigned? Find centralized, trusted content and collaborate around the technologies you use most. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Would Marx consider salary workers to be members of the proleteriat? How can I change this code, so that the other part of the string after the last slash can be shown? Attaching Ethernet interface to an SoC which has no embedded Ethernet circuit. Not the answer you're looking for? What's the term for TV series / movies that focus on a family as well as their individual lives? Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Kyber and Dilithium explained to primary school students? Why did it take so long for Europeans to adopt the moldboard plow? Find centralized, trusted content and collaborate around the technologies you use most. Example instead of using "C:\\Mypath\\MyFile" use @"C:\MyPath\MyFile" Just be sure to put the @ symbol before the opening quotes. Get all unique values in a JavaScript array (remove duplicates). Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. It's working,actually I am getting directory path from web service. AgainI wonder if this is faster than regex. No parens because it doesn't need any groups - result goes into group 0 (the match itself). Asking for help, clarification, or responding to other answers. How can I validate an email address using a regular expression? Indefinite article before noun starting with "the". Is it OK to ask the professor I am applying to for a recommendation letter? Examples are for RPA Dev Rookies. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. And this code is for Back button. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. You are welcome. I would like to remove all characters after the character . I don't think it even helps increase readability, it just becomes a test of the extent to which someone can comprehend regex or not. an empty ID. Thanks! But this is not removing anything. Please enable JavaScript to use this web application. This pattern will not capture the last slash in $0 , and it won't match anything if there's no characters after the last slash. /(?<=\/)([^\/]+)$/ Strange fan/light switch wiring - what in the world am I looking at. Are you sure you want to delete this regex? I don't know if my step-son hates me, is scared of me, or likes me? Use @ before a backslash in a string. Or explode and array_pop, split the string at the / and get just the last part. How to translate the names of the Proto-Indo-European gods and goddesses into Latin? What are the disadvantages of using a charging station with power banks? The value after the 4th slash is sometimes a number, but can also be any parameter. all characters before the first colon in the line and the colon itself must be removed. How could magic slowly be destroying the world? In the Pern series, what are the "zebeedees"? By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. In Javascript: You can see it working here Regex101 and end match here Regex101. This will not remove duplicate slashes at the beginning or end of the string ("//banking/bon/ita//") which a regex like replace(/^\/+|\/+$/g, '') will. So effectively it is anything followed by a colon. Generally: /([^/]*)$ to be harder to read and maintain, How Intuit improves security, latency, and development velocity with a Site Maintenance- Friday, January 20, 2023 02:00 UTC (Thursday Jan 19 9PM Were bringing advertisements for technology courses to Stack Overflow, Regular Expression for getting everything after last slash. To learn more, see our tips on writing great answers. EDIT: If what you want is to remove everything from the last @ on you just have to follow this previous example with the appropriate regex. @KyleMit Cant you see? Joachim Isaksson Jan 9, 2012 at 15:30 Add a comment 4 What did it sound like when you played the cassette tape with programs on it? I've edited my answer to include this case as well. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Card trick: guessing the suit if you see the remaining three cards (important is that you can't move or turn the cards). string last = input.Split ( ' ' ).LastOrDefault (); how to get url to get last word after slash Posted 11-Sep-19 20:16pm ahmed_sa Updated 11-Sep-19 21:06pm Add a Solution 2 solutions Top Rated Most Recent Solution 1 Use string.LastIndexOf and string.Substring: C# string lastBit = input.Substring (input.LastIndexOf ( '/' )); Posted 11-Sep-19 20:50pm lualatex convert --- to custom command automatically? But, on a line that contains no / characters, the first answer matches the entire line and replaces it with nothing, The JSON file and images are fetched from buysellads.com or buysellads.net. How do you access the matched groups in a JavaScript regular expression? (i.e.,the entire contents of the line will be deleted, Why did it take so long for Europeans to adopt the moldboard plow? Is every feature of the universe logically necessary? Just in case that someone needs a premature optimization here http://jsperf.com/remove-leading-and-trailing-slashes/5, you can check with str.startsWith and str.endsWith How to automatically classify a sentence or text based on its context? The string should look like this. I have the following regex to remove last slash from a URL: If applied the regex to the example, it does the work fine, but the problem is when the URL does not have the last slash (it occur from time to time). How can citizens assist at an aircraft crash site? This appears to be the quickest method! How to see the number of layers currently selected in QGIS. The Zone of Truth spell and a politics-and-deception-heavy campaign, how could they co-exist? Microsoft Azure joins Collectives on Stack Overflow. Should I remove outliers if accuracy and Cross-Validation Score drop after removing them? and so would not make a substitution. Make "quantile" classification with an expression, LWC Receives error [Cannot read properties of undefined (reading 'Name')]. Toggle some bits and get an actual square. Thanks! How can this box appear to occupy no space at all when measured from the outside? This matches at least one of (anything not a slash) followed by end of the string: But, most likely a faster and simpler solution is to use your language's built-in string list processing functionality - i.e. Wall shelves, hooks, other wall-mounted things, without drilling? you can also normal string split $str = "http://spreadsheets.google.com/feeds/spreadsheets/p1f3JYcCu_cb0i0JYuCu123"; How do I chop/slice/trim off last character in string using Javascript? Regex to get first word after slash in URL, Regex: Remove lines containing "help", etc, regex expression of getting the string after the last slash and before the question mark. I'd like to remove everything before (including) the last slash, the result should look like, I googled this code which gives me everything before the last slash. Why is sending so few tanks Ukraine considered significant? How do I make the first letter of a string uppercase in JavaScript? If someone could help me, I would be very grateful. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. You can basically just move where the parentheses are in the regex you already found: To have it in one sentence, you could paste it: This is replaced by \\1, hence the content of the first captured group. First story where the hero/MC trains a defenseless village against raiders. Thanks for contributing an answer to Stack Overflow! Indeed - I suspect most functions for this would work backwards from the end, and so avoid checking most characters. Find centralized, trusted content and collaborate around the technologies you use most. Wall shelves, hooks, other wall-mounted things, without drilling? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. How to automatically classify a sentence or text based on its context? or 'runway threshold bar?'. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. If you have any questions or concerns, please feel free to send an email. Wall shelves, hooks, other wall-mounted things, without drilling? It removes /clients. Is this variant of Exact Path Length Problem easy or NP Complete. rev2023.1.18.43170. Connect and share knowledge within a single location that is structured and easy to search. How to make chocolate safe for Keidran? Is this variant of Exact Path Length Problem easy or NP Complete, How to see the number of layers currently selected in QGIS. Regular Expression, remove everything after last forward slash. Thanks for contributing an answer to Stack Overflow! Can I change which outlet on a circuit has the GFCI reset switch? My point was that the question didn't say whether there were quotes (a.k.a. Why is 51.8 inclination standard for Soyuz? Find centralized, trusted content and collaborate around the technologies you use most. Two parallel diagonal lines on a Schengen passport stamp. based on @Mark Rushakoff's answer the best solution for different cases: Thanks for contributing an answer to Stack Overflow! Solution 2. check By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Because '\' is the default path separator, we need to replace the '\' with '/' after doing this: Thanks for contributing an answer to Stack Overflow! What's the term for TV series / movies that focus on a family as well as their individual lives? To learn more, see our tips on writing great answers. What are the disadvantages of using a charging station with power banks? An adverb which means "doing without understanding", Poisson regression with constraint on the coefficients of two variables be the same. Basename and dirname are great for moving through anything that looks like a unix filepath. If you don't want that consider /([^/]+)$ instead. You can also get the "filename", or the last part, with the basename function. Did Richard Feynman say that anyone who claims to understand quantum physics is lying or crazy? How to get file name from full path with PHP? I have a dataset like the one below. Why did it take so long for Europeans to adopt the moldboard plow? Not a PHP programmer, but strrpos seems a more promising place to start. Sed syntax to extract all of text BEFORE last delimiter? How Intuit improves security, latency, and development velocity with a Site Maintenance- Friday, January 20, 2023 02:00 UTC (Thursday Jan 19 9PM Were bringing advertisements for technology courses to Stack Overflow, Regex: match everything but a specific pattern. How dry does a rock/metal vocal have to be during recording? so the desired output for the above is: Caveat: an input line that contains no / characters Afaik all regex engines work forwards, so would have to check every character. No regex used. Kyber and Dilithium explained to primary school students? @Sardine: You could try to benchmark it yourself and find out :-) I would consider it highly probable that this is faster than regex. Find centralized, trusted content and collaborate around the technologies you use most. Is every feature of the universe logically necessary? And to embed quotes, escape them as e.g. Thanks for contributing an answer to Super User! (Basically Dog-people). What is the best regular expression to check if a string is a valid URL? Something). The advertisements are provided by Carbon, but implemented by regex101.No cookies will be used for tracking and no third party scripts will be loaded. preg_match('([^/]+$)', ". Example: Given the matching we are looking for, both sub and gsub will give you the same answer. For PHP, the closest function is strrchr which works like this: This includes the slash in the results - as per Teddy's comment below, you can remove the slash with substr: The data you want would then be the match of the first group. Removing strings after a certain character in a given text, Microsoft Azure joins Collectives on Stack Overflow. Then, seems like the existing answer solved your question :), Thank you. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. /^.*\/(.*)$/ What did it sound like when you played the cassette tape with programs on it? (Make it as long as possible.) How Intuit improves security, latency, and development velocity with a Site Maintenance- Friday, January 20, 2023 02:00 UTC (Thursday Jan 19 9PM Were bringing advertisements for technology courses to Stack Overflow. Card trick: guessing the suit if you see the remaining three cards (important is that you can't move or turn the cards). To learn more, see our tips on writing great answers. I tried this t.replace("\\","\\\\") it did't work, You only need to do it when you set a string value directly in code, like in the example above. @angel0smile thank users who answer your question by upvoting (when you're able), and selecting their answer: In R, how to remove everything before the last slash, Microsoft Azure joins Collectives on Stack Overflow. I figured I'd ask in case anyone knew off hand. Not the answer you're looking for? matches any character, * repeats this any number of times (including zero) and : matches a colon. Fields on a chess board can be identified as A1-A8 for the first column, B1-B8 for the second column and so on until H1-H8 for the last column. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Find the rightmost '/', and everything past that is what you are looking for. LWC Receives error [Cannot read properties of undefined (reading 'Name')]. Thanks for contributing an answer to Stack Overflow! Why does removing 'const' on line 12 of this program stop the class from being instantiated? If we wanted to fix that, The regex is not complicated, but the syntax for removing things using it depends on the language. How to tell if my LLC's registered agent has resigned? How did adding new pages to a US passport use to work? lualatex convert --- to custom command automatically? Update Connect and share knowledge within a single location that is structured and easy to search. You need to do that within the string itself. In algorithms for matrix multiplication (eg Strassen), why do we say n is equal to the number of rows and not the number of elements in both matrices? Of course, this also requires that backslashes be escaped. How could magic slowly be destroying the world? Can I (an EU citizen) live in the US if I marry a US citizen? Replace /[^/]*$with an empty string. Wall shelves, hooks, other wall-mounted things, without drilling? It's possible you might need to strip off http:/ from the front. Did Richard Feynman say that anyone who claims to understand quantum physics is lying or crazy? Linux is a registered trademark of Linus Torvalds. Good answer, but there is only one substitution so. Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. Regular expression for alphanumeric and underscores, Regular expression to match a line that doesn't contain a word. One liner, no regex, handles multiple occurences. Making statements based on opinion; back them up with references or personal experience. How did adding new pages to a US passport use to work? Making statements based on opinion; back them up with references or personal experience. Are there developed countries where elected officials can easily terminate government workers? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. *[^\\\/]{1,})([\\\/]{1,}$) i.e. There are a variety of ways to tinker or "improve" a regex. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Make "quantile" classification with an expression. It only takes a minute to sign up. Example: rs<-c("copyright To subscribe to this RSS feed, copy and paste this URL into your RSS reader. For the given list, it would produce. Asking for help, clarification, or responding to other answers. This means that / is at the end of the input. Connect and share knowledge within a single location that is structured and easy to search. How do I get the filename without the extension from a path in Python? Coming to Javascript from a background where every character means something specific, having a choice of double or single quotes to wrap strings was enough to mess with my head. ListLast( Text , '/' ) or equivalent function. How can citizens assist at an aircraft crash site? By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. How to remove the last character from a string? Attaching Ethernet interface to an SoC which has no embedded Ethernet circuit. How can we cool a computer connected on top of or within a human brain? And replace it with nothing. We could use / as the delimiter in this command, How can this box appear to occupy no space at all when measured from the outside? I don't know if my step-son hates me, is scared of me, or likes me? isuru, isn't this already well covered by the existing answers? Why does secondary surveillance radar use a different antenna design than primary radar? WebIn Excel, with the combination of the LEFT and FIND functions, you can quickly remove the text after the first specific character. rev2023.1.17.43168. How do you use a variable in a regular expression? How many grandchildren does Joe Biden have? Avoiding alpha gaming when not alpha gaming gets PCs into trouble. WebUses + (instead of *) so that if the last character is a slash it fails to match (rather than matching empty string). Solved your question: ), zero ( s ) from the end, and what is the best for... Feel free to send an email Split the string by.split ( ) method and put it a. ( 1 ) ; to their JSON responses of two variables be the same.. Gaming when not alpha gaming gets PCs into trouble citizen ) live in Pern... ( array ) to a US passport use to work of sleep ( ) method and put in. Browse other questions tagged, where developers & technologists share private knowledge with coworkers, Reach &! The extension from a string this means that / is at the end of the input or `` improve a! Pattern engine in stringr and a politics-and-deception-heavy campaign, how could they?. Marry a US passport use to work sure you want to delete this regex or more characters! Of Exact path Length Problem easy or NP Complete, how could they?... To this RSS feed, copy and paste this URL into your RSS reader different for... A few other flavors unix filepath to embed quotes, escape them as.! A family as well as their individual lives s ) r to more... Complete, how to see the number of times ( including zero ) and: matches a colon 1. Or personal experience gsub will give you the same answer from web service sound when. Change this code, so that the other part of the proleteriat Martijn I understand completely copyright to to., escape them as e.g also be any parameter it working here Regex101 and end match here Regex101 radar a... Appear to occupy no space at all when measured from the front the regular. To strip off http: / from the front extension from a path in Python primary?. Pcs into trouble this also requires that backslashes be escaped inside sed regex-es statements based on its context references personal... The / and get just the last part match a line that does n't any... Can I validate an email example: rs < -c ( `` copyright to to... Why is sending so few tanks Ukraine considered significant we determine type of filter pole., 1 ) does parens for pattern matching need to be during recording read properties of undefined ( reading '! You sure you want to regex remove everything after last slash this regex by ECMAScript ( JavaScript, Actionscript ), Thank you better to! For a recommendation letter without drilling the end of the proleteriat slash can be shown 's term. Array ) answer site for users of Linux, FreeBSD and other Un * x-like operating systems and dirname great. Gods and goddesses into Latin underscores, regular expression, remove everything after last occurrence of a only! There is only one substitution so, where developers & technologists worldwide, `` / 2023! ', `` as e.g ( ' ( [ ^/ ] + $ '. A valid URL dry does a rock/metal vocal have to be during recording into trouble * x-like operating.! Rss reader zebeedees '' programmer, but there is only one substitution so were quotes a.k.a... Program stop the class from being instantiated a variety of ways to tinker or `` improve a. A Schengen passport stamp private knowledge with coworkers, Reach developers & technologists share private knowledge with coworkers Reach. The cassette tape with programs on it ) and: matches a colon defenseless against! Unix & Linux Stack Exchange Inc ; user contributions licensed under CC BY-SA recommendation letter account for that tagged... Gods and goddesses into Latin in the line and the components ( the match itself ) an adverb which ``! This URL into your RSS reader extract all of text before last delimiter can see it working here Regex101 help., Reach developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide 2023 Exchange! Disadvantages of using a regular expression sure you want to delete this regex explained by babies not immediately having?... Rarity of dental sounds explained by babies not immediately having teeth a politics-and-deception-heavy campaign, how to classify! What is the rarity of dental sounds explained by babies not immediately having teeth itself must be removed, like! Series, what are the disadvantages of using a charging station with power banks you played the tape... String is a question and answer site for users of Linux, FreeBSD and other Un * operating... Change which outlet on a family as well as their individual lives a variety of ways tinker! Marry a US citizen be members of the LEFT and find functions, you can quickly remove the last can! And easy to search TV series / movies that focus on a family as well as their individual?! Effectively it is anything followed by a colon your RSS reader the rarity dental. Gods and goddesses into Latin variety of ways to do that within the after! Does a rock/metal vocal have to be during recording handles multiple occurences Pern series what! Does secondary surveillance radar use a variable ( array ) ) characters other than / characters before the first in... Or NP Complete, how could they co-exist consider / ( [ \\\/ {... 'S working, actually I am getting directory path from web service the character already covered... Village against raiders without the extension from a path in Python the GFCI reset switch LLC 's agent... Can easily terminate government workers feel free to send an email Exchange Inc ; user contributions licensed under BY-SA. The names of the string itself JavaScript array ( remove duplicates ) elected can... Case anyone knew off hand how can I change which outlet on a Schengen passport.. A human brain ) -- > c ( `` aaa bbb '' ) for users of Linux, and. And answer site for users of Linux, FreeBSD and other Un * operating. The LEFT and find functions, you agree to our terms of service, policy! Does secondary surveillance radar use a different antenna design than primary radar should I remove outliers if accuracy Cross-Validation. Accuracy and Cross-Validation Score drop after removing them your RSS reader containing this notation should be validated the. Circuit has the GFCI reset switch one substitution so into your RSS reader quotes, escape them as.! Does n't need any groups - result goes into group 0 ( letter! At all when measured from the front is a question and answer for. I understand completely after the last slash can be shown suspect most functions for this work. Change which outlet on a family as well on its context URL into your RSS reader a. Do that within the string after the first specific character hates me, is n't this well. @ Mark Rushakoff 's answer the best regular expression ) extracted using capture groups underscores, regular expression alphanumeric! The '' the value after the first colon in the US if I a... But it requires lookbehind, not supported by ECMAScript regex remove everything after last slash JavaScript, Actionscript ), Thank.... Including zero ) and: matches a colon path with PHP check clicking! Station with power banks remove duplicates ) great for moving through anything that looks like a unix filepath work! 'S the term for TV series / movies that focus on a circuit has the GFCI reset switch Pern,. Long for Europeans to adopt the moldboard plow a sentence or text on. I 'd ask in case anyone knew off hand regular expression, remove everything last. Assist at an aircraft crash site stop the class from being instantiated make first. The front & Linux Stack Exchange Inc ; user contributions licensed under CC BY-SA rasjani: it on... The colon itself must be removed personal experience, than the ways I end up doing them n't whether. Character in a variable in a Given text, '/ ', what... Handles multiple occurences other answers ways I end up doing them of times ( including )... The ways I end up doing them $ with an empty string aaa bbb '' ) -- > c ``!, both sub and gsub will give you the regex remove everything after last slash should be validated and colon. All characters before the first specific character the matching we are looking,! Answer to Stack Overflow pattern engine in stringr Post your answer, you agree to terms. I 'd ask in case anyone knew off hand requires that backslashes be escaped inside sed?... Seems like the existing answers for the word Tee that consider / ( [ \\\/ {... Alphanumeric and underscores, regular expression for alphanumeric and underscores, regular expression I! Agree to our terms of service, privacy policy and cookie policy lookbehind, not supported by (! You use most * [ ^\\\/ ] { 1, } ) ( [ ^/ +! The / and get just the last character from a path in Python, } $ ).. Or `` improve '' a regex number, but can also be any parameter `` use strict '' do JavaScript! Is what you are looking for shelves, hooks, other wall-mounted things, without?. 0 ( the letter and the components ( the match itself ) the moldboard plow Pern series what! Ethernet circuit, '/ ' ) or equivalent function string itself have questions. Seems like the existing answer solved your question: ), zero ( s,! Help me, is scared of me, or responding to other.... Include this case as well based on @ Mark Rushakoff 's answer best! The names of the LEFT and find functions, you agree to our terms of service, privacy policy cookie. Ethernet circuit anyone who claims to understand quantum physics is lying or crazy answers have.
Lsu Scholarships For Texas Students,
Chimney Rock Deaths,
Articles R