{"id":238442,"date":"2025-06-18T05:59:36","date_gmt":"2025-06-18T05:59:36","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=238442"},"modified":"2025-06-18T05:59:39","modified_gmt":"2025-06-18T05:59:39","slug":"in-c-some-of-the-following-are-legal-identifiers","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/18\/in-c-some-of-the-following-are-legal-identifiers\/","title":{"rendered":"In C++, some of the following are legal identifiers."},"content":{"rendered":"\n<p>In C++, some of the following are legal identifiers. Which? (Choose 2 right answers) Select one or more: a. Xyz b. xy_z c. 9xyz d. xyz! e. X+yz<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/06\/image-695.png\" alt=\"\" class=\"wp-image-238443\"\/><\/figure>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p><strong>Correct answers:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>a. Xyz<\/strong><\/li>\n\n\n\n<li><strong>b. xy_z<\/strong><\/li>\n<\/ul>\n\n\n\n<p><strong>Explanation:<\/strong><\/p>\n\n\n\n<p>In C++, identifiers are the names used to identify variables, functions, arrays, classes, and other user-defined elements. There are specific rules for forming valid identifiers:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>An identifier <strong>must begin<\/strong> with a letter (A\u2013Z or a\u2013z) or an underscore (_) character.<\/li>\n\n\n\n<li>Subsequent characters can include letters, digits (0\u20139), or underscores.<\/li>\n\n\n\n<li>Identifiers <strong>cannot begin with a digit<\/strong>.<\/li>\n\n\n\n<li>Identifiers <strong>cannot contain symbols<\/strong> such as <code>!<\/code>, <code>+<\/code>, <code>@<\/code>, <code>#<\/code>, etc.<\/li>\n\n\n\n<li>Keywords reserved by the language cannot be used as identifiers.<\/li>\n<\/ol>\n\n\n\n<p>Let us evaluate each option based on these rules:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>a. Xyz<\/strong><br>This is a valid identifier. It starts with a letter and contains only letters. No special characters or digits are used inappropriately.<\/li>\n\n\n\n<li><strong>b. xy_z<\/strong><br>This is also valid. It begins with a letter and includes an underscore, which is allowed.<\/li>\n\n\n\n<li><strong>c. 9xyz<\/strong><br>Invalid. Identifiers cannot begin with a digit. This breaks the first rule.<\/li>\n\n\n\n<li><strong>d. xyz!<\/strong><br>Invalid. The exclamation mark <code>!<\/code> is not allowed in identifiers.<\/li>\n\n\n\n<li><strong>e. X+yz<\/strong><br>Invalid. The plus sign <code>+<\/code> is not permitted within an identifier. It is considered an operator, not a legal character for names.<\/li>\n<\/ul>\n\n\n\n<p>Therefore, only <strong>a. Xyz<\/strong> and <strong>b. xy_z<\/strong> meet the requirements for legal identifiers in C++. These follow the language&#8217;s syntax rules for naming variables or other elements, making them safe and acceptable for use in a C++ program<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/06\/learnexams-banner5-738.jpeg\" alt=\"\" class=\"wp-image-238444\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>In C++, some of the following are legal identifiers. Which? (Choose 2 right answers) Select one or more: a. Xyz b. xy_z c. 9xyz d. xyz! e. X+yz The Correct Answer and Explanation is: Correct answers: Explanation: In C++, identifiers are the names used to identify variables, functions, arrays, classes, and other user-defined elements. There [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","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":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","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-opacity":"","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-opacity":"","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-opacity":"","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-opacity":"","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-opacity":"","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-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-238442","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/238442","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=238442"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/238442\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=238442"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=238442"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=238442"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}