Online free programming editors

Please find Online free programming editors

1. Ruby RegExp (Regular Expression) online free editor
    https://rubular.com/

2. C language online free editor
    https://www.onlinegdb.com/online_c_compiler
    https://repl.it/languages/c
    https://www.tutorialspoint.com/compile_c_online.php

3. Java language online free editor
    https://www.tutorialspoint.com/compile_java_online.php
    https://www.jdoodle.com/online-java-compiler

4. Scala language online free editor
    https://scastie.scala-lang.org/
    https://www.tutorialspoint.com/compile_scala_online.php