scala1. ``` object scala3 { def sum1(x:Int,y:Int):Int = { x

object scala3 {
def sum1(x:Int,y:Int):Int = {
  x + y
}
  val sum2 = (x:Int,y:Int) => { x+y }

  def main(args: Array[String]): Unit = {
    println(sum1(10,20))
    println(sum2(10,20))
  }
}

object scala4 {
val sum2 = (a:Int, b:Int,c:Int) => a + b + c

  def main(args: Array[String]): Unit = {
    val r = sum2(10,20, _)
    println(r(50))
    val r1 = sum2(_,20,_)
    println(r1(10,30))
  }
}