https://www.hackerrank.com/challenges/staircase/problem

Staircase - Simple.kt

import java.util.Scanner

fun staircase(n: Int): Unit {
    for (y in 1..n) {
        var line = ""
        for (x in 1..n) {
            if (x <= n-y)
                line += " "
            else
                line += "#"
        }
        System.out.println(line)
    }
}

fun main(args: Array<String>) {
    val scan = Scanner(System.`in`)
    val n = scan.nextLine().trim().toInt()
    staircase(n)
}