Download and install scala

Download and install scala link: https://docs.scala-lang.org/getting-started/index.html

Or: https://www.scala-lang.org/download/2.12.8.html

Environment configuration:

An easy, zero-setup way to run Scala programs without installing Scala is to run Scala programs in your browser using ScalaFiddle.
Take printing "Hello Scala" as an example. First open https://scalafiddle.io in the browser, then enter "println("Hello Scala")" in the middle pane, and finally click the Run button, the output will be displayed in the right pane, as shown in Figure 2 -18 shown.