发帖格式不好看，下面我沙发再发一次，谢谢指导 import java.util.Scanner; import java.math.BigInteger; import java.util.LinkedList; import java.util.Queue; public class Main {     public static void main(String[] args) {         Scanner in = new Scanner(System.in);         int n = in.nextInt();         System.out.println(solve(n));         in.close();     }     public static BigInteger solve(int n) {         BigInteger m1 = BigInteger.valueOf(0);         BigInteger m = BigInteger.valueOf(0);         BigInteger yes = BigInteger.valueOf(1);         Queue<BigInteger> queue = new LinkedList<BigInteger>();         if (n <= 3) {             return BigInteger.valueOf(1);         }         while (queue.size() < 3) {             queue.offer(m1);         }         while (n - 3 > 0) {             --n;             yes = yes.add(queue.poll());             queue.offer(yes);         }         while (!queue.isEmpty()) {             m = m.add(queue.poll());         }         return m.add(yes);     } }