{"id":2603,"date":"2021-06-05T07:00:03","date_gmt":"2021-06-05T01:30:03","guid":{"rendered":"https:\/\/www.codingbroz.com\/?p=2603"},"modified":"2021-06-22T10:58:11","modified_gmt":"2021-06-22T05:28:11","slug":"valid-username-regular-expression-solution","status":"publish","type":"post","link":"https:\/\/www.codingbroz.com\/valid-username-regular-expression-solution\/","title":{"rendered":"Valid Username Regular Expression | HackerRank Solution"},"content":{"rendered":"\n<p>Hello coders, today we are going to solve <strong>Valid Username Regular Expression HackerRank Solution<\/strong> <strong>in Java<\/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-valid.png\" alt=\"Valid Username Regular Expression\" class=\"wp-image-2604\" srcset=\"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/java-valid.png 1167w, https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/java-valid-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-662c123838a58\" 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-662c123838a58\" 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\/valid-username-regular-expression-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\/valid-username-regular-expression-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\/valid-username-regular-expression-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\/valid-username-regular-expression-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\/valid-username-regular-expression-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\/valid-username-regular-expression-solution\/#Sample_Input-2\" title=\"Sample Input\">Sample Input<\/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-7\" href=\"https:\/\/www.codingbroz.com\/valid-username-regular-expression-solution\/#Solution_%E2%80%93_Valid_Username_Regular_Expression_in_Java\" title=\"Solution &#8211; Valid Username Regular Expression in Java\">Solution &#8211; Valid Username Regular Expression in Java<\/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>You are updating the username policy on your company&#8217;s internal networking platform. According to the policy, a username is considered valid if all the following constraints are satisfied:<\/p>\n\n\n\n<ul><li>The username consists of <strong>8 <\/strong>to <strong>10 <\/strong>characters inclusive. If the username consists of less than <strong>8 <\/strong>or greater than <strong>30 <\/strong>characters, then it is an invalid username.<\/li><li>The username can only contain alphanumeric characters and underscores (_). Alphanumeric characters describe the character set consisting of lowercase characters <strong>[a-z]<\/strong>, uppercase characters <strong>[A-Z]<\/strong>, and digits <strong>[0-9]<\/strong>.<\/li><li>The first character of the username must be an alphabetic character, i.e., either lowercase character <strong>[a-z]<\/strong> or uppercase character <strong>[A-Z]<\/strong>.<\/li><\/ul>\n\n\n\n<p>For example:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td class=\"has-text-align-center\" data-align=\"center\"> <strong>Username<\/strong><\/td><td><strong>Validity<\/strong><\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">Julia<\/td><td>INVALID; Username length &lt; 8 characters<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">Samantha<\/td><td>VALID<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">Samantha_21<\/td><td>VALID<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">1Samantha<\/td><td>INVALID; Username begins with non-alphabetic character<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">Samantha?10_2A<\/td><td>INVALID; &#8216;?&#8217; character not allowed<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p>Update the value of regularExpression field in the UsernameValidator class so that the regular expression only matches with valid usernames.<\/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 an integer <strong><em>n<\/em><\/strong>, describing the total number of usernames. Each of the next <strong><em>n <\/em><\/strong>lines contains a string describing the username. The locked stub code reads the inputs and validates the username.<\/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>1 &lt;= n &lt;= 100<\/strong><\/li><li>The username consists of any printable characters.<\/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>For each of the usernames, the locked stub code prints Valid if the username is valid; otherwise Invalid each on a new line.<\/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> 8\n Julia\n Samantha\n Samantha_21\n 1Samantha\n Samantha?10_2A\n JuliaZ007\n Julia@007\n _Julia007<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Sample_Input-2\"><\/span><strong>Sample Input<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code> Invalid\n Valid\n Valid\n Invalid\n Invalid\n Valid\n Invalid\n Invalid<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Solution_%E2%80%93_Valid_Username_Regular_Expression_in_Java\"><\/span><strong>Solution &#8211;<\/strong> <strong>Valid Username Regular Expression<\/strong> <strong>in Java<\/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.Scanner;\nclass UsernameValidator {\n    \/*\n     * Write regular expression here.\n     *\/\n    public static final String regularExpression = \"^[A-Za-z]\\\\w{7,29}$\";\n}\n\n\npublic class Solution {\n    private static final Scanner scan = new Scanner(System.in);\n    \n    public static void main(String[] args) {\n        int n = Integer.parseInt(scan.nextLine());\n        while (n-- != 0) {\n            String userName = scan.nextLine();\n\n            if (userName.matches(UsernameValidator.regularExpression)) {\n                System.out.println(\"Valid\");\n            } else {\n                System.out.println(\"Invalid\");\n            }           \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\/valid-username-checker\/problem\" target=\"_blank\" data-type=\"URL\" data-id=\"https:\/\/www.hackerrank.com\/challenges\/valid-username-checker\/problem\" rel=\"noreferrer noopener\">Valid Username Regular Expression<\/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 Valid Username Regular Expression HackerRank Solution in Java.<\/p>\n","protected":false},"author":1,"featured_media":2604,"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-valid.png","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/2603"}],"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=2603"}],"version-history":[{"count":2,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/2603\/revisions"}],"predecessor-version":[{"id":3731,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/2603\/revisions\/3731"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/media\/2604"}],"wp:attachment":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/media?parent=2603"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/categories?post=2603"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/tags?post=2603"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}