{"id":2751,"date":"2021-06-06T09:44:28","date_gmt":"2021-06-06T04:14:28","guid":{"rendered":"https:\/\/www.codingbroz.com\/?p=2751"},"modified":"2021-06-22T15:50:23","modified_gmt":"2021-06-22T10:20:23","slug":"java-dequeue-solution","status":"publish","type":"post","link":"https:\/\/www.codingbroz.com\/java-dequeue-solution\/","title":{"rendered":"Java Dequeue | HackerRank Solution"},"content":{"rendered":"\n<p>Hello coders, today we are going to solve <strong>Java Dequeue HackerRank Solution<\/strong>.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1167\" height=\"675\" src=\"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/java-dequeue.png\" alt=\"Java Dequeue\" class=\"wp-image-2753\" srcset=\"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/java-dequeue.png 1167w, https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/java-dequeue-768x444.png 768w\" sizes=\"(max-width: 1167px) 100vw, 1167px\" \/><\/figure>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_65 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<label for=\"ez-toc-cssicon-toggle-item-662c7013afd0a\" class=\"ez-toc-cssicon-toggle-label\"><label class=\"ez-toc-title\">Table of Contents<\/label>\n<span class=\"ez-toc-cssicon\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #0090ff;color:#0090ff\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #0090ff;color:#0090ff\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-662c7013afd0a\" checked \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.codingbroz.com\/java-dequeue-solution\/#Problem\" title=\"Problem\">Problem<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.codingbroz.com\/java-dequeue-solution\/#Input_Format\" title=\"Input Format\">Input Format<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.codingbroz.com\/java-dequeue-solution\/#Constraints\" title=\"Constraints\">Constraints<\/a><\/li><\/ul><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.codingbroz.com\/java-dequeue-solution\/#Output_Format\" title=\"Output Format\">Output Format<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.codingbroz.com\/java-dequeue-solution\/#Sample_Input\" title=\"Sample Input\">Sample Input<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.codingbroz.com\/java-dequeue-solution\/#Sample_Output\" title=\"Sample Output\">Sample Output<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.codingbroz.com\/java-dequeue-solution\/#Explanation\" title=\"Explanation\">Explanation<\/a><\/li><\/ul><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.codingbroz.com\/java-dequeue-solution\/#Solution_%E2%80%93_Java_Dequeue\" title=\"Solution &#8211; Java Dequeue\">Solution &#8211; Java Dequeue<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Problem\"><\/span><strong>Problem<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>In computer science, a double-ended queue (dequeue, often abbreviated to deque, pronounced deck) is an abstract data type that generalizes a queue, for which elements can be added to or removed from either the front (head) or back (tail).<\/p>\n\n\n\n<p>Deque interfaces can be implemented using various types of collections such as LinkedList or ArrayDeque classes. For example, deque can be declared as:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code> Deque deque = new LinkedList&lt;&gt;();\n or\n Deque deque = new ArrayDeque&lt;&gt;();<\/code><\/pre>\n\n\n\n<p>In this problem, you are given <strong><em>N <\/em><\/strong>integers. You need to find the maximum number of unique integers among all the possible contiguous subarrays of size <strong><em>M<\/em><\/strong>.<br>Note: Time limit is <strong><em>3 <\/em><\/strong>second for this problem.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Input_Format\"><\/span><strong>Input Format<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>The first line of input contains two integers <strong>N <\/strong>and <strong>M<\/strong>: representing the total number of integers and the size of the subarray, respectively. The next line contains <strong>N <\/strong>space separated integers.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Constraints\"><\/span><strong>Constraints<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<ul><li><strong><em>1 &lt;= N &lt;= <\/em><\/strong><em><strong>100000<\/strong><\/em><\/li><li><strong><em>1 &lt;= M &lt;= <\/em><\/strong><em><strong>100000<\/strong><\/em><\/li><li><strong><em>M &lt;= N<\/em><\/strong><\/li><li>The numbers in the array will range between <strong>[10000000]<\/strong>.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Output_Format\"><\/span><strong>Output Format<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Print the maximum number of unique integers among all possible contiguous subarrays of size <strong>M<\/strong>.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Sample_Input\"><\/span><strong>Sample Input<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code> 6 3\n 5 3 5 2 3 2<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Sample_Output\"><\/span><strong>Sample Output<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code> 3<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Explanation\"><\/span><strong>Explanation<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<p>In the sample testcase, there are 4 subarrays of contiguous numbers.<\/p>\n\n\n\n<ul><li><strong><em>s1 = &lt;5,3,5&gt; &#8211; <\/em><\/strong>Has <strong>2 <\/strong>unique numbers.<\/li><li><strong><em>s2 = &lt;3,5,2&gt; &#8211; <\/em><\/strong>Has <strong>3 <\/strong>unique numbers.<\/li><li><strong><em>s3 = &lt;5,2,3&gt; &#8211; <\/em><\/strong>Has <strong>3 <\/strong>unique numbers.<\/li><li><strong><em>s4 = &lt;2,3,2&gt; &#8211; <\/em><\/strong>Has <strong>2 <\/strong>unique numbers.<\/li><\/ul>\n\n\n\n<p>In these subarrays, there are <strong><em>2,3,3,2 <\/em><\/strong>unique numbers, respectively. The maximum amount of unique numbers among all possible contiguous subarrays is <strong><em>3<\/em><\/strong>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Solution_%E2%80%93_Java_Dequeue\"><\/span><strong>Solution &#8211;<\/strong> <strong>Java Dequeue<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"java\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">import java.util.*;\n\npublic class test {\n    public static void main(String[] args) {\n        Scanner in = new Scanner(System.in);\n        Deque&lt;Integer> deque = new ArrayDeque&lt;>();\n        HashSet&lt;Integer> set = new HashSet&lt;>();\n        \n        int n = in.nextInt();\n        int m = in.nextInt();\n        int max = Integer.MIN_VALUE;\n\n        for (int i = 0; i &lt; n; i++) {\n            int input = in.nextInt();\n            \n            deque.add(input);\n            set.add(input);\n            \n            if (deque.size() == m) {\n                if (set.size() > max) max = set.size();\n                int first = deque.remove();\n                if (!deque.contains(first)) set.remove(first);\n            }\n        }\n        \n        System.out.println(max);\n    }\n}\n<\/pre>\n\n\n\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script>\n<ins class=\"adsbygoogle\"\n     style=\"display:block; text-align:center;\"\n     data-ad-layout=\"in-article\"\n     data-ad-format=\"fluid\"\n     data-ad-client=\"ca-pub-5246141430412355\"\n     data-ad-slot=\"8798433565\"><\/ins>\n<script>\n     (adsbygoogle = window.adsbygoogle || []).push({});\n<\/script>\n\n\n\n<p><strong>Disclaimer:<\/strong> The above Problem ( <strong><em><a href=\"https:\/\/www.hackerrank.com\/challenges\/java-dequeue\/problem\" target=\"_blank\" data-type=\"URL\" data-id=\"https:\/\/www.hackerrank.com\/challenges\/java-dequeue\/problem\" rel=\"noreferrer noopener\">Java Dequeue<\/a><\/em><\/strong> ) is generated by <strong>Hacker Rank<\/strong> but the Solution is Provided by <strong>CodingBroz<\/strong>. This tutorial is only for <strong>Educational<\/strong> and <strong>Learning<\/strong> Purpose.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Hello coders, today we are going to solve Java Dequeue HackerRank Solution.<\/p>\n","protected":false},"author":1,"featured_media":2753,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"default","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[9,120],"tags":[80,84,18,121],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/java-dequeue.png","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/2751"}],"collection":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/comments?post=2751"}],"version-history":[{"count":3,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/2751\/revisions"}],"predecessor-version":[{"id":3749,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/2751\/revisions\/3749"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/media\/2753"}],"wp:attachment":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/media?parent=2751"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/categories?post=2751"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/tags?post=2751"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}