{"id":36713,"date":"2005-01-13T06:58:00","date_gmt":"2005-01-13T06:58:00","guid":{"rendered":"https:\/\/blogs.msdn.microsoft.com\/oldnewthing\/2005\/01\/13\/user-interface-design-for-vending-machines-answer-to-puzzle\/"},"modified":"2005-01-13T06:58:00","modified_gmt":"2005-01-13T06:58:00","slug":"user-interface-design-for-vending-machines-answer-to-puzzle","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/oldnewthing\/20050113-00\/?p=36713","title":{"rendered":"User interface design for vending machines &#8211; answer to puzzle"},"content":{"rendered":"<p> <a href=\"http:\/\/weblogs.asp.net\/oldnewthing\/archive\/2005\/01\/12\/351398.aspx\"> Last time, we ended a discussion of vending machine design with a short puzzle<\/a>: What problems do you see with numbering the products from 1 to 99? <\/p>\n<p> I&#8217;m not saying that these are the only possible answers, but they are ones that came to mind when I thought about it. <\/p>\n<ul>\n<li>Product codes less than 10 would be ambiguous. Is a &#8220;3&#8221; a request for product number 3, or is the user just being slow at entering &#8220;32&#8221;? Solving this by adding a leading zero will not work because people are in the habit of ignoring leading zeros. <\/li>\n<li>Product codes should not coincide with product prices. If there is a bag of cookies that costs 75 cents, users are likely to type &#8220;75&#8221; when they want the cookies, even though the product code for the cookies is 23. <\/li>\n<\/ul>\n<p> <a href=\"http:\/\/ilyabirman.ru\/\">Ilya Birman<\/a> was the first to point out <a href=\"http:\/\/weblogs.asp.net\/oldnewthing\/archive\/2005\/01\/12\/351398.aspx#351447\"> the &#8220;bounce-effect&#8221; problem<\/a>, thereby ruling out product codes like 11, 22, and 33. <\/p>\n","protected":false},"excerpt":{"rendered":"<p>Last time, we ended a discussion of vending machine design with a short puzzle: What problems do you see with numbering the products from 1 to 99? I&#8217;m not saying that these are the only possible answers, but they are ones that came to mind when I thought about it. Product codes less than 10 [&hellip;]<\/p>\n","protected":false},"author":1069,"featured_media":111744,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[103],"class_list":["post-36713","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-oldnewthing","tag-non-computer"],"acf":[],"blog_post_summary":"<p>Last time, we ended a discussion of vending machine design with a short puzzle: What problems do you see with numbering the products from 1 to 99? I&#8217;m not saying that these are the only possible answers, but they are ones that came to mind when I thought about it. Product codes less than 10 [&hellip;]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts\/36713","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/users\/1069"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/comments?post=36713"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/posts\/36713\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/media\/111744"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/media?parent=36713"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/categories?post=36713"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/oldnewthing\/wp-json\/wp\/v2\/tags?post=36713"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}