Compile and Execute Scala Online

  import java.math.BigInteger
  import scala.collection.mutable.Map
  import scala.collection.mutable.Set
  object HelloWorld {
     def main(args: Array[String]) {
     def max2(x: Int, y: Int) = if (x > y) println(x) else println(y)
       max2(4,5);
         println("Hello, "+ args(0) +"!")
         var res: Int = 5;
         res = res * 3
         println(res)
         def greet() = println("Hello, world!")
         greet();
           var i = 0
            while (i < args.length) {
             println(args(i))
            i += 1
            } 
            var j = 0
        while (j < args.length) {
            if (j != 0)
             print(" ")
                print(args(j))
                j += 1
            }
         println()
         args.foreach(arg => println(arg))
         args.foreach((arg: String) => println(arg))
          args.foreach(println)
           for (arg <- args)
             println(arg)
               val big = new java.math.BigInteger("12345")
               println(big)
    
  val greetStrings = new Array[String](3)
    greetStrings(0) = "Hello"
  greetStrings(1) = ", "
  greetStrings(2) = "world!\n"
  for (i <- 0 to 2)
    print(greetStrings(i))
  greetStrings.update(0, "Hello")
  greetStrings.update(1, ", ")
  greetStrings.update(2, "world!\n")
  for (i <- 0.to(2))
    print(greetStrings.apply(i))
    greetStrings(0) = "Hello" 
    greetStrings.update(0, "Hello")
    println(greetStrings(0))
    val numNames = Array("zero", "one", "two")
    val numNames2 = Array.apply("zero", "one", "two")
         val oneTwo = List(1, 2)
  val threeFour = List(3, 4)
  val oneTwoThreeFour = oneTwo ::: threeFour
  println(""+ oneTwo +" and "+ threeFour +" were not mutated.")
  println("Thus, "+ oneTwoThreeFour +" is a new list.")
   val twoThree = List(2, 3)
   val oneTwoThree = 1 :: twoThree
   println(oneTwoThree)
 val oneTwoThreee = 1 :: 2 :: 3 :: Nil
  println(oneTwoThreee)
   val pair = (99, "Luftballons")
        println(pair._1)
        println(pair._2)
        var jetSet = Set("Boeing", "Airbus")
  jetSet += "Lear"
  println(jetSet.contains("Boeing"))
    val movieSet = Set("Hitch", "Poltergeist")
  movieSet += "Shrek"
  println(movieSet) 
    val treasureMap = Map[Int, String]()
  treasureMap += (1 -> "Go to island.")
  treasureMap += (2 -> "Find big X on ground.")
  treasureMap += (3 -> "Dig.")
  println(treasureMap(2))
  val romanNumeral = Map(
    1 -> "I", 2 -> "II", 3 -> "III", 4 -> "IV", 5 -> "V"
  )
  println(romanNumeral(4))
  def printArgs(args: Array[String]): Unit = {
    args.foreach(println)
              }
              printArgs(Array("zero", "one", "two"))
       def printArgs1(args: Array[String]): Unit = {
            var i = 0
            while (i < args.length) {
                  println(args(i))
             i += 1
               }
          }
     printArgs1(Array("zero", "one", "two"))  
     def printArgs2(args: Array[String]): Unit = {
    for (arg <- args)
      println(arg)
  }
        printArgs2(Array("zero", "one", "two"))  
         def printArgs3(args: Array[String]): Unit = {
        args.foreach(println)
  }
          printArgs3(Array("zero", "one", "two"))  
           def formatArgs(args: Array[String]) = args.mkString("\n")
            println(formatArgs(args))
     val res1 = formatArgs(Array("zero", "one", "two"))
        assert(res1 == "zero\none\ntwo")
       }
  }