题解 | #大吉大利,今晚吃鸡#
大吉大利,今晚吃鸡
https://www.nowcoder.com/practice/c9d9f9c60b4448eabc0569f80a3461bb
import java.util.Scanner; // 手工然后找到规律搞的 public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); while (sc.hasNext()) { double n = sc.nextDouble(); long m = (long)Math.pow(3.0, n) - 1; System.out.println(m); } } }