/*
 * Prints instruction to optimally move n Hanoi discs from `src` to `des`.
 */
fun hanoi(n: Int, src: Int, des: Int) {
    if (n > 0) {
        val aux = 6 - src - des
        hanoi(n-1, src, aux)
        println("move top disc from peg $src to peg $des")
        hanoi(n-1, aux, des)
    }
}

fun main(args: Array<String>) {
     val n = args[0].toInt()
     if (n > 0) hanoi(n, 1, 3)
}