Comparing fold and reduce

FoldAndReduce.kt

class FoldAndReduce {
    val appendSC = { s: String, c: Char -> s + c }
    val appendCS = { c: Char, s: String -> c + s }
    val add = { x: Int, y: Int -> x + y }
    val sub = { x: Int, y: Int -> x + y }
    val cons = { x: Int, y: List<Int> -> listOf(x, *y.toTypedArray()) }
    val appendList = { y: List<Int>, x: Int -> y + x }

    val list1 = listOf(1, 2, 3, 4, 5)
    val list1rev = list1.reversed()
    val string = "Fold And Reduce"

    fun main(args:Array<String>) {
        println("[1,2,3,4,5].reduce(+) = ${list1.reduce(add)}")
        println("[1,2,3,4,5].reduce(-) = ${list1.reduce(sub)}")
        println("[1,2,3,4,5].fold(0)(+) = ${list1.fold(0, add)}")
        println("[1,2,3,4,5].foldr(0)(+) = ${list1.foldRight(0, add)}")
        println("[1,2,3,4,5].fold(0)(-) = ${list1.fold(0, sub)}")
        println("[1,2,3,4,5].foldr(0)(-) = ${list1.foldRight(0, sub)}")
        println("")
        println("[1,2,3,4,5].reversed().reduce(+) = ${list1rev.reduce(add)}")
        println("[1,2,3,4,5].reversed().reduce(-) = ${list1rev.reduce(sub)}")
        println("[1,2,3,4,5].reversed().fold(0)(+) = ${list1rev.fold(0, add)}")
        println("[1,2,3,4,5].reversed().foldr(0)(+) = ${list1rev.foldRight(0, add)}")
        println("[1,2,3,4,5].reversed().fold(0)(-) = ${list1rev.fold(0, sub)}")
        println("[1,2,3,4,5].reversed().foldr(0)(-) = ${list1rev.foldRight(0, sub)}")
    }
}