//
// simple demo of using loops to operate on lists
//
println("type in list values (integers), quit to end")
val list = fillList()

printList(list);

println("sum is " + listCombine(list, (x,y)=>(x+y), 0))
println("product is " + listCombine(list, (x,y)=>(x*y), 1))
println("min is " + listCombine(list, (x,y) => (x min y), Int.MaxValue))
println("max is " + listCombine(list, (x,y) => (x max y), Int.MinValue))

def fillList() : List[Int] = {
  var input = readLine
  var result = List[Int]()
  while (input != "quit") {
    result = input.toInt :: result
    input = readLine
  }
  result.reverse
}

def printList(list : List[Int]) {
  for (elem <- list) 
    println(elem)
}

def listCombine(list : List[Int], 
  combine : (Int, Int) => Int, identity : Int) : Int = 
{
  var result = identity
  for (elem <- list) 
    result = combine(result, elem)
  result
}