我用的是函数递归来做的。

import java.util.*;

public class Cfb{

 static  Scanner scan=new Scanner(System.in);

 static  int n=scan.nextInt();

   public static void main(String[] args) {

        int x1 = 1;

     int s=0;

        for (int i = 1; i <= n; i++) {

        x1 = func(i);

}

     s=x1%10007;

        System.out.println(s);

   }

     public static int func(int x) {

         if (x > 2 && n<=1000000 && n>=1)

           return (func(x - 1) + func(x - 2));

         else return 1;

}

}