{"id":1912,"date":"2020-03-31T15:55:50","date_gmt":"2020-03-31T15:55:50","guid":{"rendered":"https:\/\/golangbyexamples.com\/?p=1912"},"modified":"2020-03-31T15:55:58","modified_gmt":"2020-03-31T15:55:58","slug":"pick-random-element-array-slice-go","status":"publish","type":"post","link":"https:\/\/golangbyexamples.com\/pick-random-element-array-slice-go\/","title":{"rendered":"Pick a random element in an array or slice in Go (Golang)"},"content":{"rendered":"\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_17 counter-hierarchy counter-decimal ez-toc-light-blue\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" style=\"display: none;\"><i class=\"ez-toc-glyphicon ez-toc-icon-toggle\"><\/i><\/a><\/span><\/div>\n<nav><ul class=\"ez-toc-list ez-toc-list-level-1\"><li class=\"ez-toc-page-1 ez-toc-heading-level-1\"><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/golangbyexamples.com\/pick-random-element-array-slice-go\/#Overview\" title=\"Overview\">Overview<\/a><\/li><li class=\"ez-toc-page-1 ez-toc-heading-level-1\"><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/golangbyexamples.com\/pick-random-element-array-slice-go\/#Code\" title=\"Code\">Code<\/a><\/li><\/ul><\/nav><\/div>\n<h1 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Overview\"><\/span><strong>Overview<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h1>\n\n\n\n<p class=\"has-medium-font-size\"><strong>&#8216;mat\/rand&#8217; <\/strong>package of golang contains a <strong>Intn<\/strong> function that can be used to generate a pseudo-random number between [0,n). Bracket at the end means that n is exclusive. This function can be utilized to pick a random element in an array or slice of int or string.<\/p>\n\n\n\n<p class=\"has-medium-font-size\">To know more about what pseudo-random number means, checkout this post &#8211; <a href=\"https:\/\/golangbyexamples.com\/generate-random-number-golang\">https:\/\/golangbyexamples.com\/generate-random-number-golang<\/a><\/p>\n\n\n\n<p class=\"has-medium-font-size\">Below is the signature of this method. It takes input a number n and will return a number x in range 0&lt;=x&lt;n.<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">func Intn(n int) int<\/code><\/pre>\n\n\n\n<h1 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Code\"><\/span><strong>Code<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h1>\n\n\n\n<p class=\"has-medium-font-size\">We can directly index an element in a slice of int. See below program for picking up random from a slice of int.<\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">package main\n\nimport (\n    \"fmt\"\n    \"math\/rand\"\n)\n\nfunc main() {\n    in := []int{2, 5, 6}\n    randomIndex := rand.Intn(len(in))\n    pick := in[randomIndex]\n    fmt.Println(pick)\n}<\/code><\/pre>\n\n\n\n<p class=\"has-medium-font-size\"><strong>Output:<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-prismatic-blocks\"><code class=\"language-go\">Between 2, 5 or 6<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Table of Contents OverviewCode Overview &#8216;mat\/rand&#8217; package of golang contains a Intn function that can be used to generate a pseudo-random number between [0,n). Bracket at the end means that n is&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","footnotes":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false},"categories":[1],"tags":[45,3,4,260,46],"class_list":["post-1912","post","type-post","status-publish","format-standard","hentry","category-tech","tag-array","tag-go","tag-golang","tag-pick","tag-slice"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.7 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Pick a random element in an array or slice in Go (Golang) - Welcome To Golang By Example<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/golangbyexamples.com\/pick-random-element-array-slice-go\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Pick a random element in an array or slice in Go (Golang) - Welcome To Golang By Example\" \/>\n<meta property=\"og:description\" content=\"Table of Contents OverviewCode Overview &#8216;mat\/rand&#8217; package of golang contains a Intn function that can be used to generate a pseudo-random number between [0,n). 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