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{"payload":{"allShortcutsEnabled":false,"path":"Rabin-Karp","repo":{"id":172218010,"defaultBranch":"master","name":"swift-algorithm-club","ownerLogin":"alanzhangg","currentUserCanPush":false,"isFork":true,"isEmpty":false,"createdAt":"2019-02-23T13:32:49.000Z","ownerAvatar":"https://avatars.githubusercontent.com/u/4179267?v=4","public":true,"private":false,"isOrgOwned":false},"currentUser":null,"refInfo":{"name":"master","listCacheKey":"v0:1617413853.784398","canEdit":false,"refType":"branch","currentOid":"deae79c2010d1e7341b24314819c9736cdfc4387"},"tree":{"items":[{"name":"Rabin-Karp.playground","path":"Rabin-Karp/Rabin-Karp.playground","contentType":"directory"},{"name":"README.markdown","path":"Rabin-Karp/README.markdown","contentType":"file"},{"name":"rabin-karp.swift","path":"Rabin-Karp/rabin-karp.swift","contentType":"file"}],"templateDirectorySuggestionUrl":null,"readme":{"displayName":"README.markdown","richText":"\u003carticle class=\"markdown-body entry-content container-lg\" itemprop=\"text\"\u003e\u003cdiv class=\"markdown-heading\" dir=\"auto\"\u003e\u003ch1 tabindex=\"-1\" class=\"heading-element\" dir=\"auto\"\u003eRabin-Karp string search algorithm\u003c/h1\u003e\u003ca id=\"user-content-rabin-karp-string-search-algorithm\" class=\"anchor\" aria-label=\"Permalink: Rabin-Karp string search algorithm\" href=\"#rabin-karp-string-search-algorithm\"\u003e\u003csvg class=\"octicon octicon-link\" viewBox=\"0 0 16 16\" version=\"1.1\" width=\"16\" height=\"16\" aria-hidden=\"true\"\u003e\u003cpath d=\"m7.775 3.275 1.25-1.25a3.5 3.5 0 1 1 4.95 4.95l-2.5 2.5a3.5 3.5 0 0 1-4.95 0 .751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018 1.998 1.998 0 0 0 2.83 0l2.5-2.5a2.002 2.002 0 0 0-2.83-2.83l-1.25 1.25a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042Zm-4.69 9.64a1.998 1.998 0 0 0 2.83 0l1.25-1.25a.751.751 0 0 1 1.042.018.751.751 0 0 1 .018 1.042l-1.25 1.25a3.5 3.5 0 1 1-4.95-4.95l2.5-2.5a3.5 3.5 0 0 1 4.95 0 .751.751 0 0 1-.018 1.042.751.751 0 0 1-1.042.018 1.998 1.998 0 0 0-2.83 0l-2.5 2.5a1.998 1.998 0 0 0 0 2.83Z\"\u003e\u003c/path\u003e\u003c/svg\u003e\u003c/a\u003e\u003c/div\u003e\n\u003cp dir=\"auto\"\u003eThe Rabin-Karp string search algorithm is used to search text for a pattern.\u003c/p\u003e\n\u003cp dir=\"auto\"\u003eA practical application of the algorithm is detecting plagiarism. Given source material, the algorithm can rapidly search through a paper for instances of sentences from the source material, ignoring details such as case and punctuation. Because of the abundance of the sought strings, single-string searching algorithms are impractical.\u003c/p\u003e\n\u003cdiv class=\"markdown-heading\" dir=\"auto\"\u003e\u003ch2 tabindex=\"-1\" class=\"heading-element\" dir=\"auto\"\u003eExample\u003c/h2\u003e\u003ca id=\"user-content-example\" class=\"anchor\" aria-label=\"Permalink: Example\" href=\"#example\"\u003e\u003csvg class=\"octicon octicon-link\" viewBox=\"0 0 16 16\" version=\"1.1\" width=\"16\" height=\"16\" aria-hidden=\"true\"\u003e\u003cpath d=\"m7.775 3.275 1.25-1.25a3.5 3.5 0 1 1 4.95 4.95l-2.5 2.5a3.5 3.5 0 0 1-4.95 0 .751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018 1.998 1.998 0 0 0 2.83 0l2.5-2.5a2.002 2.002 0 0 0-2.83-2.83l-1.25 1.25a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042Zm-4.69 9.64a1.998 1.998 0 0 0 2.83 0l1.25-1.25a.751.751 0 0 1 1.042.018.751.751 0 0 1 .018 1.042l-1.25 1.25a3.5 3.5 0 1 1-4.95-4.95l2.5-2.5a3.5 3.5 0 0 1 4.95 0 .751.751 0 0 1-.018 1.042.751.751 0 0 1-1.042.018 1.998 1.998 0 0 0-2.83 0l-2.5 2.5a1.998 1.998 0 0 0 0 2.83Z\"\u003e\u003c/path\u003e\u003c/svg\u003e\u003c/a\u003e\u003c/div\u003e\n\u003cp dir=\"auto\"\u003eGiven a text of \"The big dog jumped over the fox\" and a search pattern of \"ump\" this will return 13.\nIt starts by hashing \"ump\" then hashing \"The\". If hashed don't match then it slides the window a character\nat a time (e.g. \"he \") and subtracts out the previous hash from the \"T\".\u003c/p\u003e\n\u003cdiv class=\"markdown-heading\" dir=\"auto\"\u003e\u003ch2 tabindex=\"-1\" class=\"heading-element\" dir=\"auto\"\u003eAlgorithm\u003c/h2\u003e\u003ca id=\"user-content-algorithm\" class=\"anchor\" aria-label=\"Permalink: Algorithm\" href=\"#algorithm\"\u003e\u003csvg class=\"octicon octicon-link\" viewBox=\"0 0 16 16\" version=\"1.1\" width=\"16\" height=\"16\" aria-hidden=\"true\"\u003e\u003cpath d=\"m7.775 3.275 1.25-1.25a3.5 3.5 0 1 1 4.95 4.95l-2.5 2.5a3.5 3.5 0 0 1-4.95 0 .751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018 1.998 1.998 0 0 0 2.83 0l2.5-2.5a2.002 2.002 0 0 0-2.83-2.83l-1.25 1.25a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042Zm-4.69 9.64a1.998 1.998 0 0 0 2.83 0l1.25-1.25a.751.751 0 0 1 1.042.018.751.751 0 0 1 .018 1.042l-1.25 1.25a3.5 3.5 0 1 1-4.95-4.95l2.5-2.5a3.5 3.5 0 0 1 4.95 0 .751.751 0 0 1-.018 1.042.751.751 0 0 1-1.042.018 1.998 1.998 0 0 0-2.83 0l-2.5 2.5a1.998 1.998 0 0 0 0 2.83Z\"\u003e\u003c/path\u003e\u003c/svg\u003e\u003c/a\u003e\u003c/div\u003e\n\u003cp dir=\"auto\"\u003eThe Rabin-Karp algorithm uses a sliding window the size of the search pattern. It starts by hashing the search pattern, then\nhashing the first x characters of the text string where x is the length of the search pattern. It then slides the window one character over and uses\nthe previous hash value to calculate the new hash faster. Only when it finds a hash that matches the hash of the search pattern will it compare\nthe two strings it see if they are the same (to prevent a hash collision from producing a false positive).\u003c/p\u003e\n\u003cdiv class=\"markdown-heading\" dir=\"auto\"\u003e\u003ch2 tabindex=\"-1\" class=\"heading-element\" dir=\"auto\"\u003eThe code\u003c/h2\u003e\u003ca id=\"user-content-the-code\" class=\"anchor\" aria-label=\"Permalink: The code\" href=\"#the-code\"\u003e\u003csvg class=\"octicon octicon-link\" viewBox=\"0 0 16 16\" version=\"1.1\" width=\"16\" height=\"16\" aria-hidden=\"true\"\u003e\u003cpath d=\"m7.775 3.275 1.25-1.25a3.5 3.5 0 1 1 4.95 4.95l-2.5 2.5a3.5 3.5 0 0 1-4.95 0 .751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018 1.998 1.998 0 0 0 2.83 0l2.5-2.5a2.002 2.002 0 0 0-2.83-2.83l-1.25 1.25a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042Zm-4.69 9.64a1.998 1.998 0 0 0 2.83 0l1.25-1.25a.751.751 0 0 1 1.042.018.751.751 0 0 1 .018 1.042l-1.25 1.25a3.5 3.5 0 1 1-4.95-4.95l2.5-2.5a3.5 3.5 0 0 1 4.95 0 .751.751 0 0 1-.018 1.042.751.751 0 0 1-1.042.018 1.998 1.998 0 0 0-2.83 0l-2.5 2.5a1.998 1.998 0 0 0 0 2.83Z\"\u003e\u003c/path\u003e\u003c/svg\u003e\u003c/a\u003e\u003c/div\u003e\n\u003cp dir=\"auto\"\u003eThe major search method is next. More implementation details are in rabin-karp.swift\u003c/p\u003e\n\u003cdiv class=\"highlight highlight-source-swift notranslate position-relative overflow-auto\" dir=\"auto\" data-snippet-clipboard-copy-content=\"public func search(text: String , pattern: String) -\u0026gt; Int {\n // convert to array of ints\n let patternArray = pattern.flatMap { $0.asInt }\n let textArray = text.flatMap { $0.asInt }\n\n if textArray.count \u0026lt; patternArray.count {\n return -1\n }\n\n let patternHash = hash(array: patternArray)\n var endIdx = patternArray.count - 1\n let firstChars = Array(textArray[0...endIdx])\n let firstHash = hash(array: firstChars)\n\n if (patternHash == firstHash) {\n // Verify this was not a hash collision\n if firstChars == patternArray {\n return 0\n }\n }\n\n var prevHash = firstHash\n // Now slide the window across the text to be searched\n for idx in 1...(textArray.count - patternArray.count) {\n endIdx = idx + (patternArray.count - 1)\n let window = Array(textArray[idx...endIdx])\n let windowHash = nextHash(prevHash: prevHash, dropped: textArray[idx - 1], added: textArray[endIdx], patternSize: patternArray.count - 1)\n\n if windowHash == patternHash {\n if patternArray == window {\n return idx\n }\n }\n\n prevHash = windowHash\n }\n\n return -1\n}\"\u003e\u003cpre\u003e\u003cspan class=\"pl-k\"\u003epublic\u003c/span\u003e \u003cspan class=\"pl-en\"\u003efunc\u003c/span\u003e search\u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003etext\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e \u003cspan class=\"pl-smi\"\u003eString\u003c/span\u003e \u003cspan class=\"pl-kos\"\u003e,\u003c/span\u003e pattern\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e \u003cspan class=\"pl-smi\"\u003eString\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e-\u0026gt;\u003c/span\u003e \u003cspan class=\"pl-smi\"\u003eInt\u003c/span\u003e \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e\n // convert to array of ints\n \u003cspan class=\"pl-k\"\u003elet\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003epatternArray\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e pattern\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003e\u003cspan class=\"pl-en\"\u003eflatMap\u003c/span\u003e \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e $0\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003easInt \u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003elet\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003etextArray\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e text\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003e\u003cspan class=\"pl-en\"\u003eflatMap\u003c/span\u003e \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e $0\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003easInt \u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\n\n \u003cspan class=\"pl-k\"\u003eif\u003c/span\u003e textArray\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003ecount \u003cspan class=\"pl-c1\"\u003e\u0026lt;\u003c/span\u003e patternArray\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003ecount \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003ereturn\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e-\u003c/span\u003e\u003cspan class=\"pl-c1\"\u003e1\u003c/span\u003e\n \u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\n\n \u003cspan class=\"pl-k\"\u003elet\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003epatternHash\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e \u003cspan class=\"pl-en\"\u003ehash\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003earray\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e patternArray\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003evar\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003eendIdx\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e patternArray\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003ecount \u003cspan class=\"pl-c1\"\u003e-\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e1\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003elet\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003efirstChars\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e \u003cspan class=\"pl-en\"\u003eArray\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003e\u003cspan class=\"pl-en\"\u003etextArray\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e[\u003c/span\u003e\u003cspan class=\"pl-c1\"\u003e0\u003c/span\u003e\u003cspan class=\"pl-c1\"\u003e...\u003c/span\u003eendIdx\u003cspan class=\"pl-kos\"\u003e]\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003elet\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003efirstHash\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e \u003cspan class=\"pl-en\"\u003ehash\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003earray\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e firstChars\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e\n\n \u003cspan class=\"pl-k\"\u003eif\u003c/span\u003e \u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003epatternHash \u003cspan class=\"pl-c1\"\u003e==\u003c/span\u003e firstHash\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e\n // Verify this was not a hash collision\n \u003cspan class=\"pl-k\"\u003eif\u003c/span\u003e firstChars \u003cspan class=\"pl-c1\"\u003e==\u003c/span\u003e patternArray \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003ereturn\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e0\u003c/span\u003e\n \u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\n \u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\n\n \u003cspan class=\"pl-k\"\u003evar\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003eprevHash\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e firstHash\n // Now slide the window across the text to be searched\n \u003cspan class=\"pl-k\"\u003efor\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003eidx\u003c/span\u003e \u003cspan class=\"pl-k\"\u003ein\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e1\u003c/span\u003e\u003cspan class=\"pl-c1\"\u003e...\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003etextArray\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003ecount \u003cspan class=\"pl-c1\"\u003e-\u003c/span\u003e patternArray\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003ecount\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e\n endIdx \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e idx \u003cspan class=\"pl-c1\"\u003e+\u003c/span\u003e \u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003epatternArray\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003ecount \u003cspan class=\"pl-c1\"\u003e-\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e1\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003elet\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003ewindow\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e \u003cspan class=\"pl-en\"\u003eArray\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003e\u003cspan class=\"pl-en\"\u003etextArray\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e[\u003c/span\u003eidx\u003cspan class=\"pl-c1\"\u003e...\u003c/span\u003eendIdx\u003cspan class=\"pl-kos\"\u003e]\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003elet\u003c/span\u003e \u003cspan class=\"pl-s1\"\u003ewindowHash\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e \u003cspan class=\"pl-en\"\u003enextHash\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003eprevHash\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e prevHash\u003cspan class=\"pl-kos\"\u003e,\u003c/span\u003e dropped\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e \u003cspan class=\"pl-en\"\u003etextArray\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e[\u003c/span\u003eidx \u003cspan class=\"pl-c1\"\u003e-\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e1\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e]\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e,\u003c/span\u003e added\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e \u003cspan class=\"pl-en\"\u003etextArray\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e[\u003c/span\u003eendIdx\u003cspan class=\"pl-kos\"\u003e]\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e,\u003c/span\u003e patternSize\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e patternArray\u003cspan class=\"pl-kos\"\u003e.\u003c/span\u003ecount \u003cspan class=\"pl-c1\"\u003e-\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e1\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e\n\n \u003cspan class=\"pl-k\"\u003eif\u003c/span\u003e windowHash \u003cspan class=\"pl-c1\"\u003e==\u003c/span\u003e patternHash \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003eif\u003c/span\u003e patternArray \u003cspan class=\"pl-c1\"\u003e==\u003c/span\u003e window \u003cspan class=\"pl-kos\"\u003e{\u003c/span\u003e\n \u003cspan class=\"pl-k\"\u003ereturn\u003c/span\u003e idx\n \u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\n \u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\n\n prevHash \u003cspan class=\"pl-c1\"\u003e=\u003c/span\u003e windowHash\n \u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\n\n \u003cspan class=\"pl-k\"\u003ereturn\u003c/span\u003e \u003cspan class=\"pl-c1\"\u003e-\u003c/span\u003e\u003cspan class=\"pl-c1\"\u003e1\u003c/span\u003e\n\u003cspan class=\"pl-kos\"\u003e}\u003c/span\u003e\u003c/pre\u003e\u003c/div\u003e\n\u003cp dir=\"auto\"\u003eThis code can be tested in a playground using the following:\u003c/p\u003e\n\u003cdiv class=\"highlight highlight-source-swift notranslate position-relative overflow-auto\" dir=\"auto\" data-snippet-clipboard-copy-content=\" search(text: \u0026quot;The big dog jumped\u0026quot;\u0026quot;, \u0026quot;ump\u0026quot;)\"\u003e\u003cpre\u003e \u003cspan class=\"pl-en\"\u003esearch\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e(\u003c/span\u003etext\u003cspan class=\"pl-kos\"\u003e:\u003c/span\u003e \u003cspan class=\"pl-s\"\u003e\"\u003c/span\u003e\u003cspan class=\"pl-s\"\u003eThe big dog jumped\u003c/span\u003e\u003cspan class=\"pl-s\"\u003e\"\u003c/span\u003e\u003cspan class=\"pl-s\"\u003e\"\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e,\u003c/span\u003e \u003cspan class=\"pl-s\"\u003e\"\u003c/span\u003e\u003cspan class=\"pl-s\"\u003eump\u003c/span\u003e\u003cspan class=\"pl-s\"\u003e\"\u003c/span\u003e\u003cspan class=\"pl-kos\"\u003e)\u003c/span\u003e\u003c/pre\u003e\u003c/div\u003e\n\u003cp dir=\"auto\"\u003eThis will return 13 since ump is in the 13 position of the zero based string.\u003c/p\u003e\n\u003cdiv class=\"markdown-heading\" dir=\"auto\"\u003e\u003ch2 tabindex=\"-1\" class=\"heading-element\" dir=\"auto\"\u003eAdditional Resources\u003c/h2\u003e\u003ca id=\"user-content-additional-resources\" class=\"anchor\" aria-label=\"Permalink: Additional Resources\" href=\"#additional-resources\"\u003e\u003csvg class=\"octicon octicon-link\" viewBox=\"0 0 16 16\" version=\"1.1\" width=\"16\" height=\"16\" aria-hidden=\"true\"\u003e\u003cpath d=\"m7.775 3.275 1.25-1.25a3.5 3.5 0 1 1 4.95 4.95l-2.5 2.5a3.5 3.5 0 0 1-4.95 0 .751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018 1.998 1.998 0 0 0 2.83 0l2.5-2.5a2.002 2.002 0 0 0-2.83-2.83l-1.25 1.25a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042Zm-4.69 9.64a1.998 1.998 0 0 0 2.83 0l1.25-1.25a.751.751 0 0 1 1.042.018.751.751 0 0 1 .018 1.042l-1.25 1.25a3.5 3.5 0 1 1-4.95-4.95l2.5-2.5a3.5 3.5 0 0 1 4.95 0 .751.751 0 0 1-.018 1.042.751.751 0 0 1-1.042.018 1.998 1.998 0 0 0-2.83 0l-2.5 2.5a1.998 1.998 0 0 0 0 2.83Z\"\u003e\u003c/path\u003e\u003c/svg\u003e\u003c/a\u003e\u003c/div\u003e\n\u003cp dir=\"auto\"\u003e\u003ca href=\"https://en.wikipedia.org/wiki/Rabin%E2%80%93Karp_algorithm\" rel=\"nofollow\"\u003eRabin-Karp Wikipedia\u003c/a\u003e\u003c/p\u003e\n\u003cp dir=\"auto\"\u003e\u003cem\u003eWritten by \u003ca href=\"https://github.com/brbatwork\"\u003eBill Barbour\u003c/a\u003e\u003c/em\u003e\u003c/p\u003e\n\u003c/article\u003e","errorMessage":null,"headerInfo":{"toc":[{"level":1,"text":"Rabin-Karp string search algorithm","anchor":"rabin-karp-string-search-algorithm","htmlText":"Rabin-Karp string search algorithm"},{"level":2,"text":"Example","anchor":"example","htmlText":"Example"},{"level":2,"text":"Algorithm","anchor":"algorithm","htmlText":"Algorithm"},{"level":2,"text":"The code","anchor":"the-code","htmlText":"The code"},{"level":2,"text":"Additional 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