{"id":3200,"date":"2021-06-12T10:56:22","date_gmt":"2021-06-12T05:26:22","guid":{"rendered":"https:\/\/www.codingbroz.com\/?p=3200"},"modified":"2021-06-20T20:01:06","modified_gmt":"2021-06-20T14:31:06","slug":"day-eight-least-square-regression-line-solution","status":"publish","type":"post","link":"https:\/\/www.codingbroz.com\/day-eight-least-square-regression-line-solution\/","title":{"rendered":"Day 8: Least Square Regression Line | 10 Days Of Statistics | HackerRank Solution"},"content":{"rendered":"\n<p>Hello coders, today we are going to solve <strong>Day 8: Least Square Regression Line HackerRank Solution<\/strong> which is a Part of <strong>10 Days of Statistics<\/strong> Series.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1200\" height=\"677\" src=\"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/day-8-least-square-regression-solution-codingbroz.png\" alt=\"Day 8: Least Square Regression Line\" class=\"wp-image-3202\" srcset=\"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/day-8-least-square-regression-solution-codingbroz.png 1200w, https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/day-8-least-square-regression-solution-codingbroz-768x433.png 768w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/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-6640a6361b749\" 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-6640a6361b749\" 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\/day-eight-least-square-regression-line-solution\/#Objective\" title=\"Objective\">Objective<\/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\/day-eight-least-square-regression-line-solution\/#Task\" title=\"Task\">Task<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.codingbroz.com\/day-eight-least-square-regression-line-solution\/#Input_Format\" title=\"Input Format\">Input Format<\/a><\/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\/day-eight-least-square-regression-line-solution\/#Output_Format\" title=\"Output Format\">Output Format<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.codingbroz.com\/day-eight-least-square-regression-line-solution\/#Solution_%E2%80%93_Least_Square_Regression_Line\" title=\"Solution &#8211; Least Square Regression Line\">Solution &#8211; Least Square Regression Line<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.codingbroz.com\/day-eight-least-square-regression-line-solution\/#C\" title=\"C++\">C++<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Objective\"><\/span><strong>Objective<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>In this challenge, we practice using&nbsp;<em>linear regression<\/em>&nbsp;techniques.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Task\"><\/span><strong>Task<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>A group of five students enrolls in Statistics immediately after taking a Math aptitude test. Each student&#8217;s Math aptitude test score,&nbsp;<strong><em>x<\/em><\/strong>, and Statistics course grade,&nbsp;<strong><em>y<\/em><\/strong>, can be expressed as the following list of&nbsp;<strong>(<em>x<\/em>, <em>y<\/em>)<\/strong>&nbsp;points:<\/p>\n\n\n\n<ol><li><strong>(95, 85)<\/strong><\/li><li><strong>(85, 95)<\/strong><\/li><li><strong>(80, 70)<\/strong><\/li><li><strong>(70, 65)<\/strong><\/li><li><strong>(60, 70)<\/strong><\/li><\/ol>\n\n\n\n<p>If a student scored an&nbsp;<strong>80<\/strong>&nbsp;on the Math aptitude test, what grade would we expect them to achieve in Statistics? Determine the equation of the best-fit line using the least squares method, then compute and print the value of&nbsp;<strong><em>y<\/em><\/strong>&nbsp;when&nbsp;<strong><em>x<\/em> = 80<\/strong>.<\/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>There are five lines of input; each line contains two space-separated integers describing a student&#8217;s respective&nbsp;<strong><em>x<\/em><\/strong>&nbsp;and&nbsp;<strong><em>y<\/em><\/strong>&nbsp;grades:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>95 85\n85 95\n80 70\n70 65\n60 70<\/code><\/pre>\n\n\n\n<p>If you do not wish to read this information from stdin, you can hard-code it into your program.<\/p>\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 a single line denoting the answer, rounded to a scale of&nbsp;<strong>3<\/strong>&nbsp;decimal places (i.e.,&nbsp;<strong>1.234<\/strong>&nbsp;format).<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Solution_%E2%80%93_Least_Square_Regression_Line\"><\/span><strong>Solution &#8211; Least Square Regression Line<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"C\"><\/span><strong>C++<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"cpp\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">#include &lt;cmath>\n#include &lt;cstdio>\n#include &lt;vector>\n#include &lt;iostream>\n#include &lt;algorithm>\nusing namespace std;\n\ndouble reg(vector&lt;int>x, vector&lt;int>y)\n{\n    \/\/ mean\n    long sum1 = 0;\n    for(int i=0; i&lt;x.size(); i++)\n        sum1 += x[i];\n    double mean1 = (double)sum1\/x.size();\n    \n    long sum2 = 0;\n    for(int i=0; i&lt;y.size(); i++)\n        sum2 += y[i];\n    double mean2 = (double)sum2\/y.size();\n    \n    \/\/ sqre sum\n    long xsq = 0;\n    for(int i=0; i&lt;x.size(); i++)\n        xsq += (x[i]*x[i]);\n    \n    \/\/ sum: xy\n    long xy = 0;\n    for(int i=0; i&lt;x.size(); i++)\n        xy += (x[i]*y[i]);\n    \n    \/\/ finding a &amp; b;\n    double b = (5.0*xy - sum1*sum2)\/(5.0*xsq - sum1*sum1);\n    double a = mean2 - b*mean1;\n    \n    return a + b*80;\n}\n\nint main() {\n    \/* Enter your code here. Read input from STDIN. Print output to STDOUT *\/  \n    \n    vector&lt;int> x,y;\n    \n    for(auto i=0; i&lt;5; i++)\n    {\n        int p, q;\n        cin>>p;\n        x.push_back(p);\n        cin>>q;\n        y.push_back(q);\n    }\n    \n    double res = reg(x, y);\n    \n    printf(\"%0.3f\", res);\n    \n    return 0;\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>(<a href=\"https:\/\/www.hackerrank.com\/challenges\/s10-least-square-regression-line\/problem\" target=\"_blank\" rel=\"noreferrer noopener\">Least Square Regression Line<\/a>)<\/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 Day 8: Least Square Regression Line HackerRank Solution which is a Part of 10 Days of Statistics Series.<\/p>\n","protected":false},"author":1,"featured_media":3202,"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":[9,187],"tags":[189,80,81,18],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/www.codingbroz.com\/wp-content\/uploads\/2021\/06\/day-8-least-square-regression-solution-codingbroz.png","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/3200"}],"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=3200"}],"version-history":[{"count":3,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/3200\/revisions"}],"predecessor-version":[{"id":3451,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/posts\/3200\/revisions\/3451"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/media\/3202"}],"wp:attachment":[{"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/media?parent=3200"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/categories?post=3200"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.codingbroz.com\/wp-json\/wp\/v2\/tags?post=3200"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}