import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc=new Scanner(System.in); int day=sc.nextInt(); System.out.println(getCount(day)); } public static int getCount(int day){ if(day<=0 ||day>=11){ System.out.println("数据错误"); return -1; } if(day==10){ return 1; } return (getCount(day+1)+1)*2; } }