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Available in 15 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-15" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">15 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%AE%D9%88%D8%A7%D8%B1%D8%B2%D9%85%D9%8A%D8%A9_%D9%81%D9%88%D8%B1%D9%8A%D8%A9" title="خوارزمية فورية – Arabic" lang="ar" hreflang="ar" data-title="خوارزمية فورية" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Online-Algorithmus" title="Online-Algorithmus – German" lang="de" hreflang="de" data-title="Online-Algorithmus" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%A7%D9%84%DA%AF%D9%88%D8%B1%DB%8C%D8%AA%D9%85_%D8%A8%D8%B1%D8%AE%D8%B7" title="الگوریتم برخط – Persian" lang="fa" hreflang="fa" data-title="الگوریتم برخط" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Algorithme_online" title="Algorithme online – French" lang="fr" hreflang="fr" data-title="Algorithme online" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%98%A8%EB%9D%BC%EC%9D%B8_%EC%95%8C%EA%B3%A0%EB%A6%AC%EC%A6%98" title="온라인 알고리즘 – Korean" lang="ko" hreflang="ko" data-title="온라인 알고리즘" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Algoritmo_online" title="Algoritmo online – Italian" lang="it" hreflang="it" data-title="Algoritmo online" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%90%D7%9C%D7%92%D7%95%D7%A8%D7%99%D7%AA%D7%9D_%D7%9E%D7%A7%D7%95%D7%95%D7%9F" title="אלגוריתם מקוון – Hebrew" lang="he" hreflang="he" data-title="אלגוריתם מקוון" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Online-algoritme" title="Online-algoritme – Dutch" lang="nl" hreflang="nl" data-title="Online-algoritme" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%AA%E3%83%B3%E3%83%A9%E3%82%A4%E3%83%B3%E3%82%A2%E3%83%AB%E3%82%B4%E3%83%AA%E3%82%BA%E3%83%A0" title="オンラインアルゴリズム – Japanese" lang="ja" hreflang="ja" data-title="オンラインアルゴリズム" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Algorytm_online" title="Algorytm online – Polish" lang="pl" hreflang="pl" data-title="Algorytm online" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Online-algoritmi" title="Online-algoritmi – Finnish" lang="fi" hreflang="fi" data-title="Online-algoritmi" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%82%E0%B8%B1%E0%B9%89%E0%B8%99%E0%B8%95%E0%B8%AD%E0%B8%99%E0%B8%A7%E0%B8%B4%E0%B8%98%E0%B8%B5%E0%B8%AD%E0%B8%AD%E0%B8%99%E0%B9%84%E0%B8%A5%E0%B8%99%E0%B9%8C" title="ขั้นตอนวิธีออนไลน์ – Thai" lang="th" hreflang="th" data-title="ขั้นตอนวิธีออนไลน์" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9E%D0%BD%D0%BB%D0%B0%D0%B9%D0%BD_%D0%B0%D0%BB%D0%B3%D0%BE%D1%80%D0%B8%D1%82%D0%BC" title="Онлайн алгоритм – Ukrainian" lang="uk" hreflang="uk" data-title="Онлайн алгоритм" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Thu%E1%BA%ADt_to%C3%A1n_tr%E1%BB%B1c_tuy%E1%BA%BFn" title="Thuật toán trực tuyến – Vietnamese" lang="vi" hreflang="vi" data-title="Thuật toán trực tuyến" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E7%B7%9A%E4%B8%8A%E6%BC%94%E7%AE%97%E6%B3%95" 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id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Algorithm that begins on possibly incomplete inputs</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Not to be confused with <a href="/wiki/Online_and_offline" title="Online and offline">online and offline</a>.</div> <p>In <a href="/wiki/Computer_science" title="Computer science">computer science</a>, an <b>online algorithm</b><sup id="cite_ref-karp92_1-0" class="reference"><a href="#cite_note-karp92-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> is one that can process its input piece-by-piece in a serial fashion, i.e., in the order that the input is fed to the <a href="/wiki/Algorithm" title="Algorithm">algorithm</a>, without having the entire input available from the start. </p><p>In contrast, an <b>offline algorithm</b> is given the whole problem data from the beginning and is required to output an answer which solves the problem at hand. In <a href="/wiki/Operations_research" title="Operations research">operations research</a>, the area in which online algorithms are developed is called <a href="/wiki/Online_optimization" title="Online optimization">online optimization</a>. </p><p>As an example, consider the <a href="/wiki/Sorting_algorithms" class="mw-redirect" title="Sorting algorithms">sorting algorithms</a> <a href="/wiki/Selection_sort" title="Selection sort">selection sort</a> and <a href="/wiki/Insertion_sort" title="Insertion sort">insertion sort</a>: selection sort repeatedly selects the minimum element from the unsorted remainder and places it at the front, which requires access to the entire input; it is thus an offline algorithm. On the other hand, insertion sort considers one input element per iteration and produces a partial solution without considering future elements. Thus insertion sort is an online algorithm. </p><p>Note that the final result of an insertion sort is optimum, i.e., a correctly sorted list. For many problems, online algorithms cannot match the performance of offline algorithms. If the ratio between the performance of an online algorithm and an optimal offline algorithm is bounded, the online algorithm is called <a href="/wiki/Competitive_analysis_(online_algorithm)" title="Competitive analysis (online algorithm)">competitive</a>.<sup id="cite_ref-karp92_1-1" class="reference"><a href="#cite_note-karp92-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>Not every <i>offline algorithm</i> has an efficient <i>online</i> counterpart. </p><p>In grammar theory they are associated with <a href="/wiki/Straight-line_grammar" title="Straight-line grammar">Straight-line grammars</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Definition">Definition</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Online_algorithm&action=edit&section=1" title="Edit section: Definition"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Because it does not know the whole input, an online algorithm is forced to make decisions that may later turn out not to be optimal, and the study of online algorithms has focused on the quality of decision-making that is possible in this setting. <a href="/wiki/Competitive_analysis_(online_algorithm)" title="Competitive analysis (online algorithm)">Competitive analysis</a> formalizes this idea by comparing the relative performance of an online and offline algorithm for the same problem instance. Specifically, the competitive ratio of an algorithm, is defined as the worst-case ratio of its cost divided by the optimal cost, over all possible inputs. The competitive ratio of an online problem is the best competitive ratio achieved by an online algorithm. Intuitively, the competitive ratio of an algorithm gives a measure on the quality of solutions produced by this algorithm, while the competitive ratio of a problem shows the importance of knowing the future for this problem. </p> <div class="mw-heading mw-heading3"><h3 id="Other_interpretations">Other interpretations</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Online_algorithm&action=edit&section=2" title="Edit section: Other interpretations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>For other points of view on <i>online inputs to algorithms</i>, see </p> <ul><li><a href="/wiki/Streaming_algorithm" title="Streaming algorithm">streaming algorithm</a>: focusing on the amount of memory needed to accurately represent past inputs;</li> <li><a href="/wiki/Dynamic_algorithm" class="mw-redirect" title="Dynamic algorithm">dynamic algorithm</a>: focusing on the time complexity of maintaining solutions to problems with online inputs.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Examples">Examples</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Online_algorithm&action=edit&section=3" title="Edit section: Examples"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Some <i>online algorithms</i>: </p> <ul><li><a href="/wiki/Insertion_sort" title="Insertion sort">Insertion sort</a></li> <li><a href="/wiki/Perceptron" title="Perceptron">Perceptron</a></li> <li><a href="/wiki/Reservoir_sampling" title="Reservoir sampling">Reservoir sampling</a></li> <li><a href="/wiki/Greedy_algorithm" title="Greedy algorithm">Greedy algorithm</a></li> <li><a href="/wiki/Adversary_(online_algorithm)" class="mw-redirect" title="Adversary (online algorithm)">Adversary model</a></li> <li><a href="/wiki/Metrical_task_systems" class="mw-redirect" title="Metrical task systems">Metrical task systems</a></li> <li><a href="/wiki/Odds_algorithm" title="Odds algorithm">Odds algorithm</a></li> <li><a href="/wiki/Page_replacement_algorithm" title="Page replacement algorithm">Page replacement algorithm</a></li> <li><a href="/wiki/Algorithms_for_calculating_variance" title="Algorithms for calculating variance">Algorithms for calculating variance</a></li> <li><a href="/wiki/Ukkonen%27s_algorithm" title="Ukkonen's algorithm">Ukkonen's algorithm</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Online_problems">Online problems</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Online_algorithm&action=edit&section=4" title="Edit section: Online problems"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A problem exemplifying the concepts of online algorithms is the <a href="/wiki/Canadian_Traveller_Problem" class="mw-redirect" title="Canadian Traveller Problem">Canadian Traveller Problem</a>. The goal of this problem is to minimize the cost of reaching a target in a weighted graph where some of the edges are unreliable and may have been removed from the graph. However, that an edge has been removed (<i>failed</i>) is only revealed to <i>the traveller</i> when she/he reaches one of the edge's endpoints. The worst case for this problem is simply that all of the unreliable edges fail and the problem reduces to the usual <a href="/wiki/Shortest_path_problem" title="Shortest path problem">Shortest Path Problem</a>. An alternative analysis of the problem can be made with the help of competitive analysis. For this method of analysis, the offline algorithm knows in advance which edges will fail and the goal is to minimize the ratio between the online and offline algorithms' performance. This problem is <a href="/wiki/PSPACE-complete" title="PSPACE-complete">PSPACE-complete</a>. </p><p>There are many formal problems that offer more than one <i>online algorithm</i> as solution: </p> <ul><li><a href="/wiki/K-server_problem" title="K-server problem"><i>k</i>-server problem</a></li> <li><a href="/wiki/Job_shop_scheduling" class="mw-redirect" title="Job shop scheduling">Job shop scheduling problem</a></li> <li><a href="/wiki/List_update_problem" title="List update problem">List update problem</a></li> <li><a href="/wiki/Bandit_problem" class="mw-redirect" title="Bandit problem">Bandit problem</a></li> <li><a href="/wiki/Secretary_problem" title="Secretary problem">Secretary problem</a></li> <li><a href="/wiki/Search_games" class="mw-redirect" title="Search games">Search games</a></li> <li><a href="/wiki/Ski_rental_problem" title="Ski rental problem">Ski rental problem</a></li> <li><a href="/wiki/Linear_search_problem" title="Linear search problem">Linear search problem</a></li> <li>Portfolio selection problem<sup id="cite_ref-doc16_2-0" class="reference"><a href="#cite_note-doc16-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Online_algorithm&action=edit&section=5" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Dynamic_algorithm" class="mw-redirect" title="Dynamic algorithm">Dynamic algorithm</a></li> <li><a href="/wiki/Prophet_inequality" title="Prophet inequality">Prophet inequality</a></li> <li><a href="/wiki/Real-time_computing" title="Real-time computing">Real-time computing</a></li> <li><a href="/wiki/Streaming_algorithm" title="Streaming algorithm">Streaming algorithm</a></li> <li><a href="/wiki/Sequential_algorithm" title="Sequential algorithm">Sequential algorithm</a></li> <li><a href="/wiki/Online_machine_learning" title="Online machine learning">Online machine learning</a>/<a href="/wiki/Offline_learning" title="Offline learning">Offline learning</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Online_algorithm&action=edit&section=6" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-karp92-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-karp92_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-karp92_1-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFKarp1992" class="citation journal cs1">Karp, Richard M. (1992). <a rel="nofollow" class="external text" href="http://www.icsi.berkeley.edu/pubs/techreports/TR-92-044.pdf">"On-line algorithms versus off-line algorithms: How much is it worth to know the future?"</a> <span class="cs1-format">(PDF)</span>. <i>IFIP Congress (1)</i>. <b>12</b>: 416–429<span class="reference-accessdate">. Retrieved <span class="nowrap">17 August</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IFIP+Congress+%281%29&rft.atitle=On-line+algorithms+versus+off-line+algorithms%3A+How+much+is+it+worth+to+know+the+future%3F&rft.volume=12&rft.pages=416-429&rft.date=1992&rft.aulast=Karp&rft.aufirst=Richard+M.&rft_id=http%3A%2F%2Fwww.icsi.berkeley.edu%2Fpubs%2Ftechreports%2FTR-92-044.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOnline+algorithm" class="Z3988"></span></span> </li> <li id="cite_note-doc16-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-doc16_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDochow2016" class="citation book cs1">Dochow, Robert (2016). <a rel="nofollow" class="external text" href="https://www.springer.com/de/book/9783658135270"><i>Online Algorithms for the Portfolio Selection Problem</i></a>. Springer Gabler.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Online+Algorithms+for+the+Portfolio+Selection+Problem&rft.pub=Springer+Gabler&rft.date=2016&rft.aulast=Dochow&rft.aufirst=Robert&rft_id=https%3A%2F%2Fwww.springer.com%2Fde%2Fbook%2F9783658135270&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOnline+algorithm" class="Z3988"></span></span> </li> </ol></div></div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBorodin,_A.El-Yaniv,_R.1998" class="citation book cs1"><a href="/wiki/Allan_Borodin" title="Allan Borodin">Borodin, A.</a>; El-Yaniv, R. (1998). <a rel="nofollow" class="external text" href="https://www.cs.technion.ac.il/~rani/book.html"><i>Online Computation and Competitive Analysis</i></a>. Cambridge University Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-521-56392-5" title="Special:BookSources/0-521-56392-5"><bdi>0-521-56392-5</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Online+Computation+and+Competitive+Analysis&rft.pub=Cambridge+University+Press&rft.date=1998&rft.isbn=0-521-56392-5&rft.au=Borodin%2C+A.&rft.au=El-Yaniv%2C+R.&rft_id=https%3A%2F%2Fwww.cs.technion.ac.il%2F~rani%2Fbook.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOnline+algorithm" class="Z3988"></span></li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Online_algorithm&action=edit&section=7" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> 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<li><a href="/wiki/Heap_(data_structure)" title="Heap (data structure)">Heap</a></li> <li><a href="/wiki/Linked_list" title="Linked list">Linked list</a></li> <li><a href="/wiki/Queue_(abstract_data_type)" title="Queue (abstract data type)">Queue</a></li> <li><a href="/wiki/Segment_tree" title="Segment tree">Segment tree</a></li> <li><a href="/wiki/Stack_(abstract_data_type)" title="Stack (abstract data type)">Stack</a></li> <li><a href="/wiki/String_(computer_science)" title="String (computer science)">String</a></li> <li><a href="/wiki/Tree_(data_structure)" class="mw-redirect" title="Tree (data structure)">Tree</a></li> <li><a href="/wiki/Trie" title="Trie">Trie</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Algorithms and <a href="/wiki/Algorithmic_paradigm" title="Algorithmic paradigm">algorithmic paradigms</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> 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