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def combinations[T](k: Int, list: List[T]) : List[List[T]] = {
        list match {
          case Nil => Nil
          case head :: xs =>
            if (k <= 0 || k > list.length) {
              Nil
            } else if (k == 1) {
              list.map(List(_))
            } else {
              combinations(k-1, xs).map(head :: _) ::: combinations(k, xs)
            }
        }
      }
combinations: [T](Int,List[T])List[List[T]]
 case class S99Int(val i: Int) {
 
        def isPrime : Boolean = {
          if (i <= 1) false
          else if (i == 2) true
          else !(2 to (i-1)).exists(x => i % x == 0)
        }
 
        def goldbach : Option[List[Int]] = {
          val primes = (3 to i).filter(x => S99Int(x).isPrime).toList
          combinations(2, primes).find(_.foldLeft(0)((a,b) => a+b) == i)
        }
 
      }
defined class S99Int
 
implicit def i2S99(i: Int) : S99Int = new S99Int(i)
i2S99: (Int)S99Int
def printGoldbachListLimited(r: Range, lowerBound: Int) = {
        r.foreach(i => i.goldbach match {
          case Some(List(a,b)) if a > lowerBound => println("%d = %d + %d".format(i,a,b))
          case _ =>
       })
     }
printGoldbachListLimited: (Range,Int)Unit
 
def printGoldbachList(r: Range) = {
        printGoldbachListLimited(r, 0)
      }
printGoldbachList: (Range)Unit

Main.scala:1: error: expected class or object definition
def combinations[T](k: Int, list: List[T]) : List[List[T]] = {
^
Main.scala:14: error: expected class or object definition
combinations: [T](Int,List[T])List[List[T]]
^
Main.scala:29: error: expected class or object definition
defined class S99Int
^
Main.scala:31: error: expected start of definition
implicit def i2S99(i: Int) : S99Int = new S99Int(i)
         ^
Main.scala:32: error: expected class or object definition
i2S99: (Int)S99Int
^
Main.scala:33: error: expected class or object definition
def printGoldbachListLimited(r: Range, lowerBound: Int) = {
^
Main.scala:39: error: expected class or object definition
printGoldbachListLimited: (Range,Int)Unit
^
Main.scala:41: error: expected class or object definition
def printGoldbachList(r: Range) = {
^
Main.scala:44: error: expected class or object definition
printGoldbachList: (Range)Unit
^
9 errors found

Standard output is empty