ZZULIOJ 1054: 猴子吃桃，Java

1054: 猴子吃桃

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
    Scanner cin = new Scanner(System.in);int n=cin.nextInt();int result=1;for(int i=1;i<n;i++)result=(result+1)*2;System.out.println(result);}
}