1.Ruby in normaly 階乗 n! を計算する -Variable -Method -Number value -String -Structure -Output 2. How to use Ruby without using any numbers or letters 全部文字と数字を削除しましょう 1.Variable Rubyに_とか$などでVariableを作られます。 普段: my_number = 2 => _ = 2 2. Number Ruby_docsによると
![文字と数字を使わず、Rubyでプログラミングしましょう。 - Qiita](https://cdn-ak-scissors.b.st-hatena.com/image/square/a372f02a6fbaf847907bfa73d556dc2fde78a830/height=288;version=1;width=512/https%3A%2F%2Fqiita-user-contents.imgix.net%2Fhttps%253A%252F%252Fcdn.qiita.com%252Fassets%252Fpublic%252Farticle-ogp-background-412672c5f0600ab9a64263b751f1bc81.png%3Fixlib%3Drb-4.0.0%26w%3D1200%26mark64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZ3PTk3MiZoPTM3OCZ0eHQ9JUU2JTk2JTg3JUU1JUFEJTk3JUUzJTgxJUE4JUU2JTk1JUIwJUU1JUFEJTk3JUUzJTgyJTkyJUU0JUJEJUJGJUUzJTgyJThGJUUzJTgxJTlBJUUzJTgwJTgxUnVieSVFMyU4MSVBNyVFMyU4MyU5NyVFMyU4MyVBRCVFMyU4MiVCMCVFMyU4MyVBOSVFMyU4MyU5RiVFMyU4MyVCMyVFMyU4MiVCMCVFMyU4MSU5NyVFMyU4MSVCRSVFMyU4MSU5NyVFMyU4MiU4NyVFMyU4MSU4NiVFMyU4MCU4MiZ0eHQtYWxpZ249bGVmdCUyQ3RvcCZ0eHQtY29sb3I9JTIzMjEyMTIxJnR4dC1mb250PUhpcmFnaW5vJTIwU2FucyUyMFc2JnR4dC1zaXplPTU2JnM9MmI2ODAyZTgyOGQxOTdmOGQ1NzM0YWEyZjg0NWFhMzQ%26mark-x%3D142%26mark-y%3D57%26blend64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZoPTc2Jnc9NzcwJnR4dD0lNDBsZW4mdHh0LWNvbG9yPSUyMzIxMjEyMSZ0eHQtZm9udD1IaXJhZ2lubyUyMFNhbnMlMjBXNiZ0eHQtc2l6ZT0zNiZ0eHQtYWxpZ249bGVmdCUyQ3RvcCZzPThhODkxOTRlOWU1NGM0ODA2ZWQ0MzdlYTk3YTY5YTZm%26blend-x%3D142%26blend-y%3D436%26blend-mode%3Dnormal%26txt64%3DaW4g5qCq5byP5Lya56S-44OZ44O844K344OD44Kv%26txt-width%3D770%26txt-clip%3Dend%252Cellipsis%26txt-color%3D%2523212121%26txt-font%3DHiragino%2520Sans%2520W6%26txt-size%3D36%26txt-x%3D156%26txt-y%3D536%26s%3Dc515687998bd77a9f8ff552cc9bb4054)