system.out.printf function %n code example
Example: System.out.printf("%"+(n)+"s \n")
public class Staircase {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int n = in.nextInt();
String str = "#";
for (int i = 0; i < n; i++) {
System.out.printf("%" + (n) + "s \n", str);
str += "#";
}
in.close();
}
}